The theoretical yield of aluminum sulfide in grams
To find the theoretical yield of aluminum sulfide, we first need to determine which reactant is limiting. This can be done by using the given masses of aluminum and sulfur to calculate their respective moles, and then comparing the mole ratios from the balanced chemical equation.
The balanced equation for the reaction is:
2 Al + 3 S → Al2S3
Using the given masses, we can calculate the moles of each reactant:
moles of Al = 31.9 g / 26.98 g/mol = 1.18 mol
moles of S = 72.2 g / 32.06 g/mol = 2.25 mol
The mole ratio from the equation is 2:3 for Al:S, so we can see that sulfur is the limiting reactant because there are more moles of S than required to react with the available Al.
To find the theoretical yield of Al2S3, we need to use the mole ratio from the equation to calculate the moles of product that should be formed, and then convert that to grams using the molar mass of Al2S3:
moles of Al2S3 = 1.18 mol Al x (1 mol Al2S3 / 2 mol Al) = 0.59 mol Al2S3
theoretical yield of Al2S3 = 0.59 mol x 150.17 g/mol = 88.8 g
Therefore, the correct answer is (A) 88.8 g.
To calculate the theoretical yield of aluminum sulfide, we first need to determine the limiting reactant. The balanced equation for the reaction is:
2 Al + 3 S → Al₂S₃
First, we find the moles of Al and S:
- Moles of Al = 31.9 g / (26.98 g/mol) = 1.183 mol
- Moles of S = 72.2 g / (32.07 g/mol) = 2.251 mo
Now, we determine the mole ratio of Al to S:
- Mole ratio = 1.183 mol Al / 2.251 mol S = 0.526
Since the mole ratio (0.526) is less than the stoichiometric ratio (2/3 = 0.667), Al is the limiting reactant.
Now, we can calculate the moles of Al₂S₃ produced:
- Moles of Al₂S₃ = (1.183 mol Al) * (1 mol Al₂S₃ / 2 mol Al) = 0.5915 mol
Finally, we can find the theoretical yield in grams:
- Theoretical yield = (0.5915 mol Al₂S₃) * (150.16 g/mol) = 88.8 g
The theoretical yield of aluminum sulfide is 88.8 g (Option A).
To learn more about theoretical yield, click here:
brainly.com/question/14966377
#SPJ11
Which statement is incorrect for red blood cell?
A. they prefer CO2 at pH 7.35
B. they have a higher affinity for O2 compared to CO2
C. they prefer O2 at pH 7.45
D. they bind CO2 at the tissues because pp CO2 is higher at the tissues
E. they bind O2 at the lungs because pp O2 is higher at the lungs
The incorrect statement for red blood cells is A. They prefer CO2 at pH 7.35. Red blood cells have a higher affinity for CO2 compared to O2. Hence, they bind CO2 at the tissues where the partial pressure of CO2 is higher due to metabolic activity.
Similarly, they bind O2 at the lungs where the partial pressure of O2 is higher due to respiration. Therefore, options D and E are correct.
Moreover, the oxygen dissociation curve of hemoglobin is shifted to the right at lower pH, which means that at pH 7.35, the affinity of hemoglobin for oxygen is decreased, and it is more likely to release oxygen to the tissues. On the other hand, at pH 7.45, the affinity of hemoglobin for oxygen is increased, and it is more likely to bind oxygen in the lungs. Therefore, option C is also correct.
However, option A is incorrect because red blood cells actually prefer CO2 at lower pH (i.e., acidic conditions), not at pH 7.35, which is closer to neutral pH. At lower pH, the affinity of hemoglobin for CO2 is increased, which helps in the transport of CO2 from the tissues to the lungs for elimination.
Learn more about red blood cells here:
https://brainly.com/question/17890844
#SPJ11
determine the kb of an acid with a ka of 7.8x10-3. kw at 25 oc is 1x10-14
The Kb of the acid is approximately 1.28 x 10^-12.
When determining the Kb of an acid with a given Ka value of 7.8 x 10^-3, the ion product of water (Kw) can be utilized.
At a temperature of 25°C, Kw is known to be 1 x 10^-14. The relationship between Ka, Kb, and Kw is given by the equation:
Kw = Ka * Kb.
By rearranging this equation, we can find the value of Kb, which is the desired quantity.
Substituting the given values into the rearranged equation, we obtain
Kb = (1 x 10^-14) / (7.8 x 10^-3),
which simplifies to
Kb ≈ 1.28 x 10^-12
This result indicates that the Kb of the acid is approximately 1.28 x 10^-12.
This calculation is useful in determining the basicity of the acid and its reactivity in basic solutions. Additionally, the relationship between Ka, Kb, and Kw is an important concept in acid-base chemistry, and it is essential for understanding the behavior of acids and bases in various chemical reactions. Overall, this calculation is a simple yet essential example of how to determine the Kb of an acid using known values of Ka and Kw.
Know more about relationship between Ka, Kb, and Kw here:
https://brainly.com/question/15400042
#SPJ11
suppose you start with one liter of vinegar and repeatedly remove 0.14 l, replace with water, mix, and repeat. a. find a formula for the concentration after steps. b. after how many steps does the mixture contain less than 14% vinegar?
The concentration of vinegar in the mixture after n steps can be found using the formula
Cn = (0.86)^n, where Cn is the concentration of vinegar after n steps.
To find the number of steps required to reach a concentration of less than 14%,
we need to solve the equation (0.86)^n = 0.14.
Taking the logarithm of both sides gives n = log(0.14)/log(0.86), which is approximately 14.1 steps.
Therefore, after 15 steps, the mixture will contain less than 14% vinegar.
To know more about vinegar visit:
https://brainly.com/question/4239583
#SPJ11
If a non-cyclic alkane shows a molecular ion peak at m/z 492, what is the chemical formula?
Complete the formula:
CnHy
n=_____ carbon atoms
y=_____ hydrogen atoms
The molecular ion peak indicates the molecular weight of the compound. In this case, the non-cyclic alkane has a molecular weight of 492. To determine the chemical formula, we need to know the number of carbon and hydrogen atoms in the molecule.
The formula for a non-cyclic alkane is CnH2n+2. The "+2" represents the two additional hydrogen atoms needed to satisfy the valency of carbon.
To find the number of carbon atoms in the molecule, we can divide the molecular weight by the atomic weight of carbon (12.01). 492/12.01 ≈ 41.
Therefore, the chemical formula for this non-cyclic alkane is C41H84.
n= 41 carbon atoms
y= 84 hydrogen atoms.
A non-cyclic alkane, molecular ion peak, and chemical formula.
If a non-cyclic alkane shows a molecular ion peak at m/z 492, you can determine the chemical formula using the general formula for alkanes, which is CnH(2n+2).
Step 1: Use the given molar mass (492) to create an equation.
12n + (2n+2)(1) = 492
Step 2: Simplify the equation.
12n + 2n + 2 = 492
Step 3: Combine like terms.
14n + 2 = 492
Step 4: Subtract 2 from both sides.
14n = 490
Step 5: Divide by 14 to find the number of carbon atoms (n).
n = 490 / 14
n = 35 carbon atoms
Step 6: Calculate the number of hydrogen atoms (y) using the alkane formula.
y = 2n + 2
y = 2(35) + 2
y = 70 + 2
y = 72 hydrogen atoms
So, the chemical formula for the non-cyclic alkane with a molecular ion peak at m/z 492 is CnHy, where n=35 carbon atoms and y=72 hydrogen atoms. Your answer: C35H72
Visit here to know more about molecular weight:
brainly.com/question/27988184
#SPJ11
create a comic strip retelling the story of the survivors in the holocaust. Include important characters, exciting events, conflict and resolution.
Answer:
The Holocaust was a tragic event that took place during World War II. Many people were persecuted and killed because of their race, religion, or ethnicity. Despite the atrocities that took place, there were survivors who managed to escape and rebuild their lives.
One of the most important characters in the story of the Holocaust survivors is Anne Frank, who kept a diary of her experiences while in hiding from the Nazis. Other important characters include Oskar Schindler, a German businessman who saved the lives of many Jews by employing them in his factory, and Raoul Wallenberg, a Swedish diplomat who saved thousands of Hungarian Jews from deportation to concentration camps.
The story of the survivors is filled with conflict and resolution. Many faced immense danger and struggled to stay alive, while others risked their own lives to help them. The end of the war brought a resolution to the conflict, but the survivors still faced many challenges as they tried to rebuild their lives.
Overall, the story of the survivors in the Holocaust is a testament to the human spirit and the ability to persevere in the face of unimaginable hardship.
Explanation:
draw the structure of a phosphatidyl choline that contains glycerol, oleic acid, stearic acid, and choline.
Phosphatidylcholine is a type of phospholipid that is commonly found in cell membranes. It is composed of a glycerol backbone, two fatty acid chains (one oleic acid and one stearic acid), a phosphate group, and a choline molecule.
To draw the structure of a phosphatidylcholine that contains glycerol, oleic acid, stearic acid, and choline, follow these steps:
1. Start by drawing the glycerol backbone, which consists of a central carbon atom with three hydroxyl (-OH) groups attached to it.
2. Attach the two fatty acid chains to the glycerol backbone. The oleic acid should be attached to the first carbon atom of the glycerol, while the stearic acid should be attached to the third carbon atom.
3. Draw a phosphate group attached to the second carbon atom of the glycerol backbone.
4. Finally, attach a choline molecule to the phosphate group. The choline molecule consists of a nitrogen atom attached to three methyl groups and a hydroxyl group.
Your final structure of Phosphatidylcholine should look like this:
Oleic acid - O - CH2 - CH - CH2 - C - O - CH2 - CH - (glycerol backbone) - CH - CH2 - COOH
|| ||
|| ||
OH OH
|
P
|
O-
|
CH2 - CH2 - N(CH3)3 - OH
For more such questions on Phosphatidylcholine.
https://brainly.com/question/1258845#
#SPJ11
express sp in terms of molar solubility, , for the salts with the given formulas.ab(s) sp= ab2(s) sp= ab3(s) sp= a3b2(s) sp=
Sp in terms of molar solubility for ab(s) is s², ab₂(s) is 4s₃, ab₃(s) is 27s⁴, and a₃b₂(s) is 108s⁵.
1. For AB(s):
Let the molar solubility of AB be 's'. When it dissolves, it forms A+ and B- ions. So the equilibrium concentrations are:
[A+] = s
[B-] = s
Ksp = [A+][B-] = (s)(s) = s²
2. For AB2(s):
Let the molar solubility of AB2 be 's'. When it dissolves, it forms A+ and 2B- ions. So the equilibrium concentrations are:
[A+] = s
[B-] = 2s
Ksp = [A+][B-]² = (s)(2s)² = 4s³
3. For AB3(s):
Let the molar solubility of AB3 be 's'. When it dissolves, it forms A+ and 3B- ions. So the equilibrium concentrations are:
[A+] = s
[B-] = 3s
Ksp = [A+][B-]³ = (s)(3s)³ = 27s⁴
4. For A3B2(s):
Let the molar solubility of A3B2 be 's'. When it dissolves, it forms 3A+ and 2B- ions. So the equilibrium concentrations
[A+] = 3s
[B-] = 2s
Ksp = [A+]^3[B-]² = (3s)³(2s)² = 108s⁵
Learn more about molar solubility:
https://brainly.com/question/27132799
#SPJ11
calculate the concentration of i−i− in a solution obtained by shaking 0.16 mm kiki with an excess of agcl(s)agcl(s) .
The I- ion concentration in the solution produced by shaking 0.16 mM KI with an excess of AgCl(s) is 0.16 M.
How to determine ion concentration?The solubility product constant for AgCl is given by:
Ksp = [Ag+][Cl-] = 1.77 x 10⁻¹⁰
Since AgCl is an ionic solid, it dissociates in water to produce Ag+ and Cl- ions:
AgCl(s) ⇌ Ag+(aq) + Cl-(aq)
When AgCl is added to the KI solution, a precipitation reaction occurs:
Ag+(aq) + I-(aq) ⇌ AgI(s)
The Ksp expression for AgCl can be used to calculate the concentration of Ag+ ions produced when AgCl dissolves in the solution:
Ksp = [Ag+][Cl-] = [Ag+]([Ag+] + [I-])
Since AgCl is considered to be insoluble, the concentration of [Ag+] can be assumed to be very small and can be neglected in the expression. Therefore, the concentration of [I-] can be approximated to be equal to the concentration of [Cl-]:
Ksp = [Ag+][Cl-] = [Cl-]²
Solving for [Cl-]:
[Cl-] = √(Ksp) = √(1.77 x 10⁻¹⁰) = 1.33 x 10⁻⁵ M
Since the KI solution is a 0.16 M solution, the concentration of [I-] can be approximated to be 0.16 M (assuming that the solubility of KI is much greater than AgCl). Therefore, the concentration of [I2-] can be calculated using the following equation:
[I2-] = 2[Ag+] = 2[Cl-] = 2(1.33 x 10⁻⁵) = 2.66 x 10⁻⁵ M
Thus, the concentration of I- ions in the solution obtained by shaking 0.16 mM KI with an excess of AgCl(s) is 0.16 M.
Find out more on ion concentration here: https://brainly.com/question/29301321
#SPJ1
Why does the carbonyl stretching frequency in the IR spectrum of camphor occur near 1740 cm-1 whereas that of acetophenone (C6H5COCH3) is found at 1680 cm-1 and that for cyclohexanone is found at 1710 cm-1?
The carbonyl stretching frequency in the IR spectrum of camphor occurs near 1740 cm-1, while that of acetophenone is found at 1680 cm-1 and cyclohexanone at 1710 cm-1, primarily due to differences in the electron density and the steric environment around the carbonyl group in these compounds.
In camphor, the carbonyl group is part of a rigid bicyclic structure, which results in less electron delocalization and reduced conjugation. This causes a higher carbonyl stretching frequency, as there is less stabilization of the carbonyl bond, leading to a value near 1740 cm-1.
In acetophenone, the carbonyl group is conjugated with the phenyl ring, which increases electron density around the carbonyl group and stabilizes the bond. This results in a lower stretching frequency, found at 1680 cm-1.
In cyclohexanone, the carbonyl group is in a less-conjugated environment compared to acetophenone but more so than in camphor, causing the stretching frequency to fall in between, at around 1710 cm-1.
Know more about carbonyl stretching frequency here:
https://brainly.com/question/31570822
#SPJ11
When hydrogen chloride gas is added to water, the products are hydronium ions and chloride ions. Explain why, according to the Brønsted-Lowry and Lewis models, water can be described as a base in the reaction.
When hydrogen chloride gas is added to water, the products are hydronium ions and chloride ions and as the hydrogen ion is an acceptor, water is described as a Bronsted-Lowry base.
Generally according to concept of Bronsted-Lowry theory," acid is defined as a substance which donates an H⁺ ion or a proton and forms its conjugate base and the base is defined as a substance which accepts an H⁺ ion or a proton and forms its conjugate acid".
And now we can see that a hydrogen ion usually gets transferred from the HCl molecule to the H₂O molecule to give chloride ions and hydronium ions. And it is also clear that the hydrogen ion donor, HCl acts as a Bronsted-Lowry acid and also as a hydrogen ion acceptor, H₂O is a Bronsted-Lowry base.
Learn more about Bronsted Lowry acids and bases from the link given below.
https://brainly.com/question/14407412
#SPJ1
5. Imagine that we perform this ballistic pendulum experiment again, but we reverse the pendulum such that it no longer catches the ball. Instead, the ball hits the pendulum and bounces off.a. Would the energy transferred from the ball to the pendulum be greater or lesser than the energy transferred in your earlier trials? (3 pts) Hint: When we reverse the pendulum so that it cannot catch the ball, what type of collision is it?b. Would the angle that the pendulum swings be greater or lesser than the angle from your earlier trials? (2 pts)
In the modified ballistic pendulum experiment you described, the energy transferred from the ball to the pendulum would be lesser than in your earlier trials.
This is because when the ball bounces off the pendulum, it is an elastic collision, where some kinetic energy is retained by the ball after the collision, unlike the inelastic collision when the pendulum catches the ball.
a. If we reverse the pendulum such that it cannot catch the ball, the collision between the ball and the pendulum would be an elastic collision. In an elastic collision, the total kinetic energy of the system is conserved. Therefore, the energy transferred from the ball to the pendulum would be the same as in the earlier trials.
b. The angle that the pendulum swings would be greater than the angle from earlier trials. This is because in an elastic collision, the momentum of the system is conserved. Since the ball would bounce off the pendulum with the same speed at which it hit the pendulum, it would transfer more momentum to the pendulum. As a result, the pendulum would swing to a greater angle.
Learn more about pendulum here:
https://brainly.com/question/14759840
#SPJ11
If 56.0g of N2 gas occupies 44.8L under standard conditions, then what is the mass of 134.4L of H2 gas under the same conditions?
What mass of NH3 will be formed by the reaction between the two gases above? Write the complete balanced reaction first.
Answer:
12.09528g [tex]H_{2}[/tex]
68.12208g [tex]NH_{3}[/tex]
Explanation:
[tex]n = \frac{V}{V_{m} } \\ = \frac{134.4}{22.4} \\ = 6 mol H_{2}[/tex]
[tex]n=\frac{m}{M} \\m= nM\\=(6)(2.051588)\\=12.09528g H_{2}[/tex]
[tex]N_{2} : NH_{3} \\ 1 : 2\\2:x\\x= 4mol NH_{3} \\\\n = \frac{m}{M} \\m=nM\\=(4)(17.03052)\\=68.12208g NH_{3}[/tex]
how much heat is involved when 68.0 g of n2 are reacted in the reaction: 2n2(g) 5o2(g) 2h2o(l) → 4hno3(aq) δh° = -256 kj
Amount of heat involved is: 311KJ
To calculate the heat involved in this reaction, we can use the following equation:
ΔH = n × ΔH°
where ΔH is the heat involved in the reaction, n is the number of moles of N₂ reacted, and ΔH° is the standard enthalpy change for the reaction.
First, we need to calculate the number of moles of N₂ reacted. We can do this by dividing the mass of N₂ by its molar mass:
n(N₂) = m(N₂) / M(N₂) = 68.0 g / 28.014 g/mol = 2.427 mol N₂
Given equation:
2N₂(g)+ 5O₂(g) + 2H₂O(l) → 4HNO₃(aq)
so, 2mols of N₂ produces -256kj heat
2.427 moles N₂ produces = 256*2.427/2 = -311KJ heat
To know more about heat here:
https://brainly.com/question/30603212#
#SPJ11
In a galvanic cell, a spontaneous redox reaction occurs. However, the reactants are separated such that the transfer of electrons is forced to occur across a wire. The resulting electricity is measured in volts (V\rm V) and is the sum of the potentials of the oxidation and reduction half-reactions:
E?cell=E?red+E?ox{E^\circ}_{\rm cell} = {E^\circ}_{\rm red}+ {E^\circ}_{\rm ox}
Which is sometimes also written as:
E?cell=E?red(cathode)?E?red(anode){E^\circ}_{\rm cell} = {E^\circ}_{\rm red}{(\rm cathode)} - {E^\circ}_{\rm red}(\rm anode)
A table of standard reduction potentials gives E?red{E^\circ}_{\rm red}values for common half-reactions.
Reduction half-reaction E?E^\circ(V\rm V)
Ag+(aq)+e??Ag(s)\rm Ag^+{(aq)}+e^- \rightarrow Ag{(s)} 0.80
Cu2+(aq)+2e??Cu(s)\rm Cu^{2+}{(aq)}+2e^- \rightarrow Cu{(s)} 0.34
Ni2+(aq)+2e??Ni(s)\rm Ni^{2+}{(aq)}+2e^- \rightarrow Ni{(s)} ?-0.26
Fe2+(aq)+2e??Fe(s)\rm Fe^{2+}{(aq)}+2e^- \rightarrow Fe{(s)} ?-0.45
Zn2+(aq)+2e??Zn(s)\rm Zn^{2+}{(aq)}+2e^- \rightarrow Zn{(s)} ?-0.76
By reversing any of these reduction half-reactions, you get the corresponding oxidation half-reaction, for which E?ox{E^\circ}_{\rm ox}has the opposite sign of E?red{E^\circ}_{\rm red}.
Part A
Calculate the standard potential for the following galvanic cell:
Ni(s) | Ni2+(aq) | Ag+(aq) | Ag(s)\rm Ni (s)~ | ~ Ni^{2+}{(aq)}~ | ~Ag^{+}{(aq)}~ |~ Ag {(s)}
Express your answer to three significant figures and include the appropriate units.
Part B
In the context of the nickel-silver cell described in Part A, match each of the following descriptions to the anode or cathode.
Drag the appropriate items to their respective bins.
Cathode or Anode
a) Ni b) Ag c) gain mass d) losses mass e) positive electrode f) negative electrode g) attracts electrons h)stronger reducing agent.
Part A: E°cell = 0.80 V - (-0.26 V) = 1.06 V, The standard potential for the given galvanic cell is 1.06 V.
Part B: Anode: a) Ni, e) negative electrode, d) loses mass, h) stronger reducing agent and Cathode: b) Ag, f) positive electrode, c) gain mass, g) attracts electrons.
Part A:
To calculate the standard potential for the given galvanic cell, we use the formula first, we need to identify the cathode and anode in the cell. The cathode is where reduction occurs, and the anode is where oxidation occurs.
From the given half-reactions:
E°cell = E°red(cathode) - E°red(anode)
From the table of standard reduction potentials, we have:
E°red(Ni2+(aq) + 2e⁻ → Ni(s)) = -0.26 V
E°red(Ag+(aq) + e⁻ → Ag(s)) = 0.80 V
Since Ag has a higher reduction potential, it will act as the cathode and Ni will act as the anode. Now, we can plug the values into the formula:
E°cell = 0.80 V - (-0.26 V) = 1.06 V
Therefore, the standard potential for the given galvanic cell is 1.06 V.
Part B:
a) Ni - anode
b) Ag - cathode
c) gain mass - cathode
d) losses mass - anode
e) positive electrode - cathode
f) negative electrode - anode
g) attracts electrons - cathode
h) stronger reducing agent - cathode
So we can say that :
Anode: a) Ni, e) negative electrode, d) loses mass, h) stronger reducing agent
Cathode: b) Ag, f) positive electrode, c) gain mass, g) attracts electrons
To learn more about electrons, click here:
brainly.com/question/28977387
#SPJ11
how much heat is produced in burning 2 mol of ch4 inder stnadard conditions if reactants and prodcuts ar brought to 298 K and H2O(l) is formed?
496.8 kJ mol⁻¹ heat is produced in burning 2 mol of CH₄ inter standard conditions if reactants and products are brought to 298 K and H2O(l) is formed.
The balanced chemical equation for the burning of CH₄ (methane) is:
CH₄(g) + 2O₂(g) ⇔ CO₂(g) + 2H₂O(l)
According to the equation, for every 1 mol of CH₄ that is burned, 2 mol of H₂O(l) is formed. Therefore, if 2 mol of CH₄ is burned, 4 mol of H₂O(l) is formed.
To calculate the amount of heat produced in the reaction, we need to use the standard enthalpy of formation values for the reactants and products. The standard enthalpy of formation is the change in Hess's Law that occurs when 1 mol of a substance is formed from its elements in their standard states at a specified temperature and pressure (usually 298 K and 1 atm).
Using the standard enthalpy of formation values, we can calculate the heat of reaction (ΔHrxn) using the following equation:
ΔHrxn = ∑nΔHf(products) - ΣnΔHf(reactants)
where ΣnΔHf is the sum of the standard enthalpies of formation for the products and reactants, respectively, and n is the stoichiometric coefficient for each substance in the balanced equation.
For the reaction given, the standard enthalpy of formation values are:
ΔHf(CH₄) = -74.8 kJ mol⁻¹
ΔHf(O₂) = 0 kJ mol⁻¹
ΔHf(CO₂) = -393.5 kJ mol⁻¹
ΔHf(H₂O) = -285.8 kJ mol⁻¹
Substituting these values into the equation, we get:
ΔHrxn = [2(-285.8 kJ mol⁻¹)] - [(-74.8 kJ mol⁻¹) + 2(0 kJ mol⁻¹)]
= -571.6 kJ mol⁻¹ - (-74.8 kJ mol⁻¹)
ΔHrxn = -496.8 kJ mol⁻¹
This means that for every 2 mol of CH₄ that is burned, 496.8 kJ of heat is produced. Since the reaction is carried out at standard conditions (298 K and 1 atm), the heat produced is equal to the change in enthalpy (ΔH) of the reaction. Therefore, if 2 mol of CH₄ is burned, 496.8 kJ mol⁻¹ of heat is produced.
Learn more about Hess's Law here
https://brainly.com/question/16994235
#SPJ11
496.8 kJ mol⁻¹ heat is produced in burning 2 mol of CH₄ inter standard conditions if reactants and products are brought to 298 K and H2O(l) is formed.
The balanced chemical equation for the burning of CH₄ (methane) is:
CH₄(g) + 2O₂(g) ⇔ CO₂(g) + 2H₂O(l)
According to the equation, for every 1 mol of CH₄ that is burned, 2 mol of H₂O(l) is formed. Therefore, if 2 mol of CH₄ is burned, 4 mol of H₂O(l) is formed.
To calculate the amount of heat produced in the reaction, we need to use the standard enthalpy of formation values for the reactants and products. The standard enthalpy of formation is the change in Hess's Law that occurs when 1 mol of a substance is formed from its elements in their standard states at a specified temperature and pressure (usually 298 K and 1 atm).
Using the standard enthalpy of formation values, we can calculate the heat of reaction (ΔHrxn) using the following equation:
ΔHrxn = ∑nΔHf(products) - ΣnΔHf(reactants)
where ΣnΔHf is the sum of the standard enthalpies of formation for the products and reactants, respectively, and n is the stoichiometric coefficient for each substance in the balanced equation.
For the reaction given, the standard enthalpy of formation values are:
ΔHf(CH₄) = -74.8 kJ mol⁻¹
ΔHf(O₂) = 0 kJ mol⁻¹
ΔHf(CO₂) = -393.5 kJ mol⁻¹
ΔHf(H₂O) = -285.8 kJ mol⁻¹
Substituting these values into the equation, we get:
ΔHrxn = [2(-285.8 kJ mol⁻¹)] - [(-74.8 kJ mol⁻¹) + 2(0 kJ mol⁻¹)]
= -571.6 kJ mol⁻¹ - (-74.8 kJ mol⁻¹)
ΔHrxn = -496.8 kJ mol⁻¹
This means that for every 2 mol of CH₄ that is burned, 496.8 kJ of heat is produced. Since the reaction is carried out at standard conditions (298 K and 1 atm), the heat produced is equal to the change in enthalpy (ΔH) of the reaction. Therefore, if 2 mol of CH₄ is burned, 496.8 kJ mol⁻¹ of heat is produced.
Learn more about Hess's Law here
https://brainly.com/question/16994235
#SPJ11
Sodium borohydride (NaBH4) is a very selective reagent. Which functional groups can sodium borohydride reduce? Choose all that apply.I. KetoneII. AldehydeIII. EsterIV. Carboxylic Acid
Sodium borohydride is a highly selective reagent that can reduce ketones, aldehydes, and esters, but cannot reduce carboxylic acids. Sodium borohydride (NaBH4) is a highly selective reagent that is commonly used as a reducing agent in organic chemistry. It is used to reduce various functional groups to their corresponding alcohols.
The functional groups that can be reduced by sodium borohydride include ketones, aldehydes, and esters. However, carboxylic acids cannot be reduced by sodium borohydride.
The reduction of ketones and aldehydes by sodium borohydride is a well-known reaction that is often used in synthetic organic chemistry. The reduction of these functional groups involves the transfer of a hydride ion (H-) from sodium borohydride to the carbonyl carbon, resulting in the formation of a new alcohol group.
Similarly, esters can also be reduced by sodium borohydride to form alcohols. However, the reduction of esters is slower than that of ketones and aldehydes due to the presence of the bulky ester group.
On the other hand, carboxylic acids cannot be reduced by sodium borohydride because they are already at their lowest oxidation state. Instead, carboxylic acids can be converted to their corresponding esters or amides, which can then be reduced by sodium borohydride.
To know more about Sodium borohydride refer here:
https://brainly.com/question/31321350#
#SPJ11
Consider the following equilibrium system in a closed vessel. N2O4 is a colourless gas while NO2 is red/brown gas.
N204 (g) ⇌ 2 NO2 (g) AH = +57.2 kJ/mol
Predict what will happen to the colour of the gas mixture in the vessel (lighten, darken) if :
a) More N204 is added to the vessel
b) The volume of the vessel is increased
c) The system is cooled down
The colour of the gas mixture in the vessel will darken if more N₂O₄ is added to the vessel, if the volume of the vessel is increased, and if the system is cooled down.
The given reaction is an endothermic reaction as indicated by the positive enthalpy change. When N₂O₄ is heated, it decomposes into NO₂ gas which is red/brown in colour. On the other hand, when NO₂ gas is cooled down or the pressure is increased, it forms N₂O₄ which is a colourless gas. Therefore, when the equilibrium shifts towards the reactants, the gas mixture in the vessel will lighten, and when the equilibrium shifts towards the products, the gas mixture will darken.
(a) If more N₂O₄ is added to the vessel, the concentration of N₂O₄ will increase, causing the equilibrium to shift towards the products to maintain equilibrium. Thus, the gas mixture in the vessel will darken due to the increased concentration of NO₂ gas.
(b) If the volume of the vessel is increased, the equilibrium will shift towards the side with more moles of gas to maintain equilibrium. In this case, the volume is increased on the reactant side, where there is only one mole of gas, while there are two moles of gas on the product side. Thus, the equilibrium will shift towards the products, resulting in the gas mixture in the vessel darkening.
(c) If the system is cooled down, the equilibrium will shift towards the side that produces heat. In this case, since the reaction is endothermic, the equilibrium will shift towards the reactants, resulting in the gas mixture in the vessel lightening as the concentration of NO₂ gas decreases.
Learn more about endothermic reaction here:
https://brainly.com/question/23184814
#SPJ11
How many grams of KOH are contained in 400. mL of 0.250 M KOH solution?
a) 8.98 g
b) 89.8 g
c) 35.1 g
d) 5.61 g
e) 12.4 g
The correct answer is (d) 5.61 g.
To calculate the grams of KOH in a 400 mL of 0.250 M KOH solution, we can follow the given steps:
Convert the volume from milliliters (mL) to liters (L): 400 mL = 0.4 L.
Use the molarity formula:
moles of solute = molarity × volume in liters.
Here, the molarity of the solution is given as 0.250 M, and the volume is 0.4 L.
moles of KOH = 0.250 M × 0.4 L = 0.1 moles.
Convert moles to grams using the molar mass of KOH (39.1 g/mol for K, 15.999 g/mol for O, and 1.008 g/mol for H):
The molar mass of KOH is (39.1 + 15.999 + 1.008) g/mol = 56.107 g/mol.
grams of KOH = 0.1 moles × 56.107 g/mol = 5.61 g.
Therefore, the grams of KOH in 400 mL of 0.250 M KOH solution is 5.61 g.
So, the correct answer is (d) 5.61 g.
Know more about molarity here:
https://brainly.com/question/13601876
#SPJ11
Which of the following atoms has the highest first ionization energy?a. Nab. Kc. Scd. Rb
Scandium (Sc) has the highest first ionization energy among the given atoms.
To determine this, we should understand that ionization energy is the energy required to remove an electron from an atom. Generally, ionization energy increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table. The reason is that as we move across a period, the nuclear charge increases, holding the electrons more tightly, and as we move down a group, the electrons are farther away from the nucleus, making them easier to remove.
Sc has the highest ionization energy because of the poor shielding of the d-orbital, which causes the Zeff of Sc to increase. Hence, increasing the ionization energy.
To learn more about ionization energy, visit: https://brainly.com/question/28385102
#SPJ11
Scandium (Sc) has the highest first ionization energy among the given atoms.
To determine this, we should understand that ionization energy is the energy required to remove an electron from an atom. Generally, ionization energy increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table. The reason is that as we move across a period, the nuclear charge increases, holding the electrons more tightly, and as we move down a group, the electrons are farther away from the nucleus, making them easier to remove.
Sc has the highest ionization energy because of the poor shielding of the d-orbital, which causes the Zeff of Sc to increase. Hence, increasing the ionization energy.
To learn more about ionization energy, visit: https://brainly.com/question/28385102
#SPJ11
sort the alkyl halide used to its substitution pattern:1-bromobutane primary 4 2-bromobutane secondary 2-bromo-2-methylbutane tertiary
So, the sorted alkyl halides based on their substitution pattern are: 1-bromobutane (primary), 2-bromobutane (secondary), and 2-bromo-2-methylbutane (tertiary).
What factors affect Alkyl Substitution?The given alkyl halides are 1-bromobutane (primary), 2-bromobutane (secondary), and 2-bromo-2-methylbutane (tertiary). Here's the sorting process:
1. Primary alkyl halide: 1-bromobutane
- This is a primary alkyl halide because the carbon atom bonded to the halogen (bromine) is attached to only one other carbon atom.
2. Secondary alkyl halide: 2-bromobutane
- This is a secondary alkyl halide because the carbon atom bonded to the halogen (bromine) is attached to two other carbon atoms.
3. Tertiary alkyl halide: 2-bromo-2-methylbutane
- This is a tertiary alkyl halide because the carbon atom bonded to the halogen (bromine) is attached to three other carbon atoms.
To know more about Substitution:
https://brainly.com/question/31417178
#SPJ11
explain what is different about the molecules that provides a difference in your answers to questions 6 and 7. (hint: this has to do with the geometries around the various carbon atoms,)
In questions 6 and 7, we are comparing two different molecules that have the same molecular formula but different structures. Specifically, we are comparing cis-2-butene and trans-2-butene.
The difference between these two molecules lies in the geometry around the carbon-carbon double bond. In cis-2-butene, the two methyl groups (CH3) are on the same side of the double bond, while in trans-2-butene, the two methyl groups are on opposite sides of the double bond.
This difference in geometry leads to different physical and chemical properties of the two molecules, including differences in boiling point, melting point, reactivity, and stereochemistry. For example, cis-2-butene has a higher boiling point than trans-2-butene due to its greater polarity caused by the proximity of the two methyl groups on the same side. Additionally, the two isomers may react differently in certain chemical reactions due to differences in steric hindrance and orientation of functional groups relative to the double bond.
Therefore, the differences in the geometries of the carbon atoms in cis-2-butene and trans-2-butene are what provide a difference in the properties and reactivity of these molecules.
A firkin is an old British unit of volume. How many firkins are there in 825 in3? Some equality statements which may be helpful are: 1 barrel = 4 firkins (exact) 1 gallon = 231.0 in3 1 gallon = 3.78 L 1 barrel = 42.0 gallons.
There are approximately 0.34 firkins in 825 in³.
To find how many firkins are in 825 in³, we need to follow these steps:
1. Convert 825 in³ to gallons using the conversion factor 1 gallon = 231.0 in³.
2. Convert the gallons to barrels using the conversion factor 1 barrel = 42.0 gallons.
3. Convert the barrels to firkins using the conversion factor 1 barrel = 4 firkins.
Step 1: Convert 825 in³ to gallons:
825 in³ * (1 gallon / 231.0 in³) = 3.57 gallons (approximately)
Step 2: Convert 3.57 gallons to barrels:
3.57 gallons * (1 barrel / 42.0 gallons) = 0.085 barrels (approximately)
Step 3: Convert 0.085 barrels to firkins:
0.085 barrels * (4 firkins / 1 barrel) = 0.34 firkins (approximately)
So, there are approximately 0.34 firkins in 825 in³.
Learn more about barrels conversion : https://brainly.com/question/12817310
#SPJ11
onsider the following reaction occurring at 298 K: CaCO3(s) = CaO(s) + CO2(g) The following table shows standard thermodynamic quantities for each product and reactant at 298 K. Substance AH; (kJ/mol) AG; (kJ/mol) Sº (J/mol · K) CaCO3(s) - 1207.6 - 1129.1 91.7 CaO(s) -634.9 -603.3 38.1 CO2(g) -393.5 --394.4 213.8 Show that the reaction is not spontaneous under standard conditions by calculating A Grxn. Use the AG; values from the given table. Express your answer in kilojoules to one decimal place. 「 VO ΑΣΦ ? AGPxn kJ Submit Previous Answers Request Answer If CaCO3 is placed in an evacuated flask, what partial pressure of CO2 will be present when the reaction reaches equilibrium? Express your answer in atmospheres to three significant figures. V AED ? P = atm Submit Request Answer Part C Can the reaction be made more spontaneous by an increase or decrease in temperature?
To calculate the A GPxn, we can use the formula A GPxn = ΣA G°f(products) - ΣA G°f(reactants), where A G°f is the standard free energy of formation.
Plugging in the values from the table, we get:
A GPxn = (-603.3 kJ/mol + (-394.4 kJ/mol)) - (-1129.1 kJ/mol)
A GPxn = -8.6 kJ/mol
Since A Grxn is negative, the reaction would be spontaneous under standard conditions. However, since A GPxn is only slightly negative (-8.6 kJ/mol), the reaction would not proceed to completion without some external driving force.
If CaCO3 is placed in an evacuated flask, the partial pressure of CO2 at equilibrium can be calculated using the equilibrium constant, Kp. The equilibrium constant can be expressed as:
Kp = (P CO2)^x, where x is the coefficient of CO2 in the balanced equation (1 in this case)
We can then use the formula A Grxn = -RT ln Kp to solve for P CO2:
A GPxn = -RT ln Kp
-8.6 kJ/mol = -(8.314 J/mol·K)(298 K) ln(P CO2)
ln(P CO2) = 3.307
P CO2 = e^3.307 = 27.3 atm
Therefore, the partial pressure of CO2 at equilibrium would be 27.3 atm.
The spontaneity of the reaction can be affected by a change in temperature. We can use the equation A GPxn = A Hrxn - TΔSrxn to see how the free energy change varies with temperature. If we increase the temperature, the TΔSPxn term becomes more favorable (i.e. more positive), which can offset the positive A Hrxn term, resulting in a more negative A GPxn and a more spontaneous reaction.
Therefore, increasing the temperature can make the reaction more spontaneous. On the other hand, decreasing the temperature can make the reaction less spontaneous.
To know more about standard free energy :
https://brainly.com/question/13421376
#SPJ11
what is the molarity of a solution containing 16.4 g of kcl in 254 ml of solution?
The molarity of the solution containing 16.4 g of KCl in 254 ml of solution is 0.866 M. Molarity is defined as the number of moles of solute per liter of solution.
To calculate the molarity of the solution, we first need to determine the number of moles of KCl present in the solution:Number of moles = Mass / Molar mass
Number of moles = 16.4 g / 74.55 g/mol = 0.22 mol
Volume = 254 ml / 1000 ml/L = 0.254 L
Calculate the molarity using the formula:Molarity = Number of moles / Volume
Molarity = 0.22 mol / 0.254 L = 0.866 M
Learn more about molarity: https://brainly.com/question/30404105
#SPJ11
Which of the following represents the overall transformation when a carboxylic acid is converted to an ester? a. The combining of the fragments which remain after the loss of -OH from the carboxylic acid and - from the alcohol. b. The combining of the fragments which remain after the loss of -OH from the alcohol and H from the carboxylic acid.
c. The combining of the fragments which remain after the loss of an oxygen from a carboxyl group and two hydrogens from ammonia or an amine.
d. The combining of the fragments which remain after the loss of oH from the carboxylic acid and from ammonia or an amine.
The combining of the fragments which remain after the loss of -OH from the alcohol and H from the carboxylic acid represents the overall transformation when a carboxylic acid is converted to an ester. This process is called esterification. Therefor the option B is correct.
The combination of the parts left over after the loss of -OH from the alcohol and H from the carboxylic acid represents the complete transformation when a carboxylic acid is transformed into an ester.
Esterification is a typical reaction in organic chemistry that describes this process. A carboxylic acid and an alcohol react with the help of an acid catalyst to produce an ester and water during esterification.
The creation of a new C-O bond between the oxygen of the alcohol and the carbonyl carbon of the carboxylic acid drives the reaction. The -OH group of the carboxylic acid and the -H group of the alcohol are removed and the remaining pieces are joined to create the ester.
The production of many different chemicals, including plasticizers, perfumes and flavors, depends on this interaction. In general, esterification is a fundamental organic chemical reaction with several industrial and commercial uses.
To know more about esterification,
https://brainly.com/question/28118164
Calculate the pH of a solution containing an amphetamine concentration of 245 mg/Amphetamine (C9H13N) is a weak base with a pKb of 4.2.
The pH of the solution containing 245 mg/L of amphetamine is approximately 9.87.
The pH of the solution containing 245 mg/L of amphetamine (C₉H₁₃N) can be calculated using the following steps:
Convert the concentration of amphetamine from mg/L to mol/L:
245 mg/L ÷ 135.21 g/mol =[tex]1.811 * 10^{-3[/tex] mol/L
Calculate the concentration of hydroxide ions ([OH⁻]) using the base dissociation constant (Kb):
Kb = [BH⁺][OH⁻]/[B][tex]10^{-pKb[/tex] = [OH⁻][B]/[BH⁺][tex]10^{-4.2[/tex] = [OH⁻]²/([C₉H₁₃N][H₂O])Assuming that [OH⁻] << [C₉H₁₃N], the equation simplifies to:
[OH⁻] ≈ √(Kb[C₉H₁₃N]) = √(2.51 × 10⁻⁵ × 1.811 × 10⁻³) = 7.43 × 10⁻⁵ mol/LCalculate the concentration of hydrogen ions ([H+]) using the equation:
Kw = [H⁺][OH⁻]
10⁻¹⁴ = [H⁺][7.43 × 10⁻⁵]
[H⁺] = 1.35 × 10⁻¹⁰ mol/L
Calculate the pH using the equation:
pH = -log[H⁺]
pH = -log(1.35 × 10⁻¹⁰) = 9.87
Therefore, the pH of the solution containing 245 mg/L of amphetamine is approximately 9.87. Since the pKb of amphetamine is relatively low, it behaves as a weak base and the resulting pH of the solution is basic.
Learn More about pH
https://brainly.com/question/26424076
#SPJ4
are salts and alkali's fine chemicals
Answer:
Yes
Explanation:
A fine chemical is defined as "Single, pure, and complex chemicals that are only produced in small amounts by multi-purpose plants".
Determine [oh−][oh−] of a solution that is 0.230 mm in hco3−hco3−.
The [OH⁻][OH⁻] of a solution that is 0.230 mM in HCO₃⁻ can be calculated using the equilibrium expression for the bicarbonate ion.
The chemical equation for the dissociation of bicarbonate ion is:
HCO₃⁻ + H₂O ⇌ H₂CO₃ + OH⁻
The equilibrium constant expression for this reaction can be written as:
K = [H₂CO₃][OH⁻] / [HCO₃⁻]
Since the concentration of H₂CO₃ is negligible in this case, we can assume that [H₂CO₃] ≈ 0. Therefore, the equilibrium constant expression can be simplified as:
K = [OH⁻][HCO₃⁻]
We can rearrange this equation to solve for [OH⁻]:
[OH⁻] = K / [HCO₃⁻]
The equilibrium constant for this reaction (K) is 2.4 × 10⁻⁴ at 25°C.
Substituting the values given in the problem, we get:
[OH⁻] = (2.4 × 10⁻⁴) / 0.230 = 1.04 × 10⁻³ M
Therefore, the [OH⁻][OH⁻] of the solution is 1.04 × 10⁻⁶.
learn more about equilibrium here:
https://brainly.com/question/30807709
#SPJ11
in an experiment, 0.25 mol of nh3 is formed when 0.5 mol of n2 is reacted with 0.5 mol of h2. what is the percent yield
The percent yield for this experiment is approximately 75%. The percent yield is the actual yield of a reaction divided by the theoretical yield, multiplied by 100. In this case, we need to first find the theoretical yield of NH3 that should have been produced based on the amount of N2 and H2 that were reacted.
The balanced chemical equation for the reaction is:
N2 + 3H2 → 2NH3
From the given information, you have reacted 0.5 mol N₂ with 0.5 mol H₂. To find the limiting reactant, compare the mole ratios:
For N₂: 0.5 mol N₂ × (2 mol NH₃ / 1 mol N₂) = 1 mol NH₃ (theoretical yield)
For H₂: 0.5 mol H₂ × (2 mol NH₃ / 3 mol H₂) ≈ 0.333 mol NH₃ (theoretical yield)
Since the theoretical yield for H₂ is smaller, H₂ is the limiting reactant. The maximum amount of NH₃ that can be formed is 0.333 mol. The actual yield is given as 0.25 mol NH₃. Now, calculate the percent yield:
Percent Yield = (Actual Yield / Theoretical Yield) × 100
Percent Yield = (0.25 mol / 0.333 mol) × 100 ≈ 75%
To know more about reaction visit :-
https://brainly.com/question/28984750
#SPJ11
calculate the ratio of the effusion rate of oxygen gas (o2) to that of sulfur dioxide gas (so2). express your answer in decimal form and calculate your answer to at least four sig figs.
The ratio of effusion rate of O₂ to SO₂ is 2.526
What is effusion rate?Effusion rate refers to the speed at which a gas passes through a small opening and enters a vacuum or an area of lower pressure.. It depends on the size of the hole, the pressure of the gas, and the molecular weight of the gas. Lighter gases effuse faster than heavier gases. The effusion rate is directly proportional to the velocity of the gas molecules, which is in turn proportional to the square root of the temperature of the gas.
Equation:Effusion rate of a gas is inversely proportional to the square root of its molar mass.
The molar mass of O₂ is 2 × 15.999 g/mol = 31.998 g/mol.
The molar mass of SO₂ is 32.066 g/mol + 2 × 15.999 g/mol = 64.064 g/mol.
The ratio of their effusion rates is:
√(64.064 g/mol) / √(31.998 g/mol) = 2.526
Rounded to four significant figures, the ratio is 2.526.
To know more about effusion rate, click here
https://brainly.com/question/8804761
#SPJ1