Answer:
B. equal numbers of molecules
Explanation:
Using 1.8x10-5 for the Ka for acetic acid, along with the weight of sodium acetate and volume of acetic acid used to prepare the buffer, calculate the expected pH of the buffer. Show your work for full credit. How well does it compare to the observed value
Answer:
pH = 4.95
Explanation:
The buffer was created using 4.0082g sodium acetate, mixed with 10.0 mL of 3.0 M acetic acid and 90 mL of deionized water.
Using H-H equation for acetic buffer:
pH = pKa + log [Acetate] / [Acetic acid]
Where pH is the pH of the buffer
pKa = -log Ka = 4.74
[] Are molar concentration of each specie -The volume of the solution is 100mL = 0.1L-:
[Sodium acetate] = 4.0082g * (1mol / 82.03g) = 0.04886 moles / 0.1L
= 0.4886M
[Acetic acid] = 3.0M * (10mL / 100mL) = 0.300M
pH = 4.74 + log [0.4886M] / [0.300M] =
pH = 4.95
The initial pressure of 0.31 moles of gas in a drum is 742 torr. If gas is added to the drum and the final pressure is 759 torr, how many moles of gas are in the drum? Hint: for this problem, you do not have an equation in the Introduction section, but based on the relationship between pressure and volume, what can you determine about the relationship between pressure and the number of moles?
Answer:
0.32 mole
Explanation:
From the question given above, the following data were obtained:
Initial mole (n₁) = 0.31 mole
Initial pressure (P₁) = 742 torr
Final pressure (P₂) = 759 torr
Final mole (n₂) =?
The final mole of the gas in the drum can be obtained as follow:
P₁/n₁ = P₂/n₂
742 / 0.31 = 759 / n₂
Cross multiply
742 × n₂ = 0.31 × 759
742 × n₂ = 235.29
Divide both side by 742
n₂ = 235.29 / 742
n₂ = 0.32 mole
Thus, the final mole of the gas in the drum is 0.32 mole
What is the independent variable in this experiment? (Look at the photo)
Answer:
A) Temperature
Explanation:
The independent variable is the variable that the researcher changes. In this case, that's the temperature because there is hot, warm, and cold.
The food dye is the constant.
The water and time it takes for dye to mix are the dependent variable since they depend on the independent variable (the temperature)
How many moles of aluminum oxide will be produced from 0.50 mol of oxygen?
4 Al + 3 O2→ 2 Al2O3
Answer:
[tex]\boxed {\boxed {\sf \frac {1}{3} \ mol \ Al_2O_3 \approx 0.34 \ mol \ Al_2O_3}}[/tex]
Explanation:
We will use stoichiometry to solve this problem. The reaction given has a formula of
[tex]4Al+3O_2 \rightarrow 2Al_2O_3[/tex]
The coefficients tell us the number of moles necessary for the reaction.
The reaction requires 3 moles of oxygen to produce 2 moles of aluminum oxide. We can make a ratio.
[tex]\frac {3 \ mol \ O_2}{ 2\ mol \ Al_2O_3}}[/tex]
Since we are doing the reaction with 0.5 moles of oxygen, we multiply the ratio by that number.
[tex]0.5 \ mol \ O_2 *\frac {3 \ mol \ O_2}{ 2 \ mol \ Al_2O_3}}[/tex]
Flip the ratio so the moles of oxygen cancel each other out.
[tex]0.5 \ mol \ O_2 *\frac {2 \ mol \ Al_2O_3}{ 3 \ mol \ O_2}}[/tex]
[tex]0.5 *\frac {2 \ mol \ Al_2O_3}{ 3 }[/tex]
[tex]\frac {1 \ mol \ Al_2O_3}{ 3 }[/tex]
[tex]\frac {1}{3} \ mol \ Al_2O_3 = 0.33333 \ mol \ Al_2O_3 \approx 0.34 \ mol \ Al_2O_3[/tex]
0.5 moles of oxygen produces 1/3 or approximately 0.34 moles of aluminum oxide.
Which letter indicates the most sudden change in temperature
Answer:
J 9. , indicates the most sudden change in temperature
A gas with a volume of 4.0 L at a pressure of 0.9 atm is allowed to expand until the pressure drops to 0.20 atm. What is the new volume?
Answer: 25
Explanation:
The new volume will be 18 L
What is volume?The volume of a dry gas of a given mass was inversely proportional to its pressure at constant temperature, according to Boyle's law. At moderate pressures and temperatures, most gases behave like ideal gases.
Calculation of new volume is shown as below:
The new volume of can be calculated by using Boyle's law.
[tex]P_{1} V_{1} = P_{2} V_{2}[/tex]
It is given that, [tex]P_{1}[/tex] = 0.9 atm. [tex]V_{1}[/tex] = 4 L, [tex]P_{2}[/tex] = 0.20 atm
Now, put the values of given data in above equation.
[tex]V_{2}[/tex] = [tex]P_{1}V_{1}[/tex] / [tex]P_{2}[/tex].
[tex]V_{2}[/tex] = (0.9) ×4 / 0.20
= 3.6 / 0.20
= 18 L
therefore, the new volume will be 18 L.
To know more about volume.
https://brainly.com/question/2098026.
#SPJ2
How are nuclear fission and nuclear fusion similar?
A. Both processes combine smaller nuclei into larger nuclei.
B. Both processes convert mass into energy.
C. Both processes are used to produce electrical power.
D. Both processes occur in stars.
Answer:
C. Both processes convert mass into energy.
_____________refers to the soil that is frozen solid all year round, and does not even melt in the summer.
Use this website to answer the question: https://thewildclassroom.com/biomes/artictundra-2/
Question 5 options:
verglas
glaze
permafrost
frost
Answer:
Permafrost is any part of the ground that remains completely frozen or colder
______ is the movement of sediment from one place to another
Answer:
ErosionExplanation:
Erosion is the movement of sediment from one place to another. Erosion is the mechanical process of wearing or grinding somethin down. It condition in which the earth’s surface is worn away by the action of water and wind.
Therefore, the final answer is Erosion.
why Bohr's theory was inadequate?
Label the marrow, spongy bone, and cortical bone on this bone image.
Explanation:
this is the correct answer
just down of compact bone there is spongy bone
mark me
Lemon and Orange contains Limonene. What difference they have from the angle of
stereo chemistry? Describe by drawing their structures?
What is the final molarity of a solution when 250 mL H2O is added to 150 mL
0,040 M NaOH(aq)?
Answer:
0.015M is the final molarity of the NaOH solution
Explanation:
A solution of 0.040M NaOH is diluted from 150mL to 250mL + 150mL = 400mL. That means the solution is diluted:
400mL / 150mL = 2.667 times.
As the original solution has a concentration of 0.040M, the diluted solution has a concentration of:
0.040M / 2.667 =
0.015M is the final molarity of the NaOH solutionChemistry, 50 points!!! Will also mark brainliest if you answer everything
Answer:
1. 2Al + Cl2 = Al2Cl2
2 TiCl4 + 2Na = Ti + 2NaCl2
3. H2O2 = H2O + O2
4. Na2S + 2HCl = H2S + 2NaCl
5. Mg(OH)2 + 2HCl = MgCl2 + 2H2O
1. 3O2 = 2O3
A water treatment tablet contains 20.0 mg of tetraglycine hydroperiodide, 40.0% of which is available as soluble iodine. If two tablets are used to treat 1.00 liter of drinking water, what is the concentration in ppm of iodine in the treated water
Answer:
[tex]16\ \text{ppm}[/tex]
Explanation:
Mass of one tablet = 20 mg
Mass of two tablets = [tex]2\times 20=40\ \text{mg}[/tex]
Percent that is soluble in water = 40%
Mass of tablet that is soluble in water = [tex]0.4\times 40=16\ \text{mg}[/tex]
So, mass of solute is [tex]16\ \text{mg}[/tex]
Density of water = 1 kg/L
Volume of water = 1 L
So, mass of 1 L of water is [tex]1\times 1=1\ \text{kg}=1000\ \text{g}[/tex]
PPM is given by
[tex]\dfrac{\text{Mass of solute}}{\text{Mass of solvent}}\times 10^6=\dfrac{16\times 10^{-3}}{1000}\times 10^6\\ =16\ \text{ppm}[/tex]
Hence, the concentration of iodine in the treated water [tex]16\ \text{ppm}[/tex].
what is the answer to this question?
Answer:
A
Explanation:
According to Charles Law, volume is directly proportional to absolute temperature so because temperature is being decreased in this case, the volume will also decrease.
Use the following information to calculate the solubility product constant, Ksp, for CuCl. A saturated solution of CuCl in water was prepared and filtered. From the filtrate, 1.0 L was measured out into a beaker and evaporated to dryness. The solid CuCl residue recovered in the beaker was found to weigh 0.041g.
A. Ksp =1.7 × 10¯9
B. Ksp = 1.7 × 10¯7
C. Ksp = 1.7 × 10¯5
D. Ksp = 4.3 × 10¯4
E. Ksp = 2.1 × 10¯2
Answer:
B. Ksp = 1.7 × 10¯⁷
Explanation:
Hello there!
In this case, for this solubility equilibrium problem, we first need to set up the chemical reaction describing the dissolution of the involved salt, CuCl:
[tex]CuCl(s)\rightleftharpoons Cu^+(aq)+Cl^-(aq)[/tex]
Next, we write the corresponding equilibrium expression:
[tex]Ksp=[Cu^+][Cl^-][/tex]
Now, we need to calculate the concentrations of copper (I) and chloride ions at equilibrium; thus, given that 0.041 g of this solid is completely dissolved in 1.0 L of solution, we can firstly calculate the moles present in the solution:
[tex]n_{CuCl}=0.041gCuCl*\frac{1molCuCl}{99gCuCl} =4.14x10^-4mol[/tex]
Afterwards, since all the species in the reaction, CuCl, Cu+ and Cl- are in a 1:1:1 mole ratio, we realize that those moles correspond to ions in the solution, so their concentrations are:
[tex][Cu^+]=[Cl^-]=\frac{4.14x10^{-4}mol}{1.0L}= 4.14x10^{-4}M[/tex]
Then, we compute the Ksp by plug this value in the equilibrium expression:
[tex]Ksp=(4.14x10^{-4})(4.14x10^{-4})=1.7x10^{-7}[/tex]
Thus, the answer would be B. Ksp = 1.7 × 10¯⁷.
Regards!
1. State how increasing the temperature of a gas changes its volume, assuming pressure is held
constant.
Explanation:
the volume and temperature of a gas have a ditect relationship,as the temperature increases the volume also increases when pressure is held constand, heating the gas increases the kinetic energy of the particles or atoms,causing the gas to expand until the pressure returns to its original value
Help I do not understand.
Answer:
158.5g Zn are produced
Explanation:
To solve this question we have to find the moles of Aluminium. With the moles of Aluminium and the balanced reaction we can find the moles of Zn and its mass as follows:
Moles Al -Molar mass: 26.98g/mol
43.6g Al* (1mol/26.98g) = 1.616 moles Al
Moles Zn:
1.616 moles Al * (3mol Zn / 2mol Al) =
2.424 moles Zn are produced
Mass Zn -Molar mass: 65.38g/mol-
2.424 moles Zn * (65.38g / mol) =
158.5g Zn are producedreport speech in grammar
Explanation:
I don't understand the question
Answer:
Reported speech is often called indirect speech. Reported speech is the speech in which someone says that someone told something.
For example:
1. The English teacher said that she would take our test on Monday.
2. Mr. James said that he was not feeling well due to dry weather.
Did you observe the tense of the reported speech? It is in past form. In reported speech always use past tense.
How much energy would be released as 95.0 g of acetic acid crystallized?
Answer:
-18.54kJ of energy would be released
Explanation:
The enthalpy of crystallization is defined as the heat released when 1 mole of a substance change its state from liquid to solid. The ΔHcrystallization of acetic acid is -11.72kJ/mol (ΔHcrystallization = - ΔHfusion).
To solve this question we must convert the mass of acetic acid to moles in order to find the heat released:
Moles acetic acid -Molar mass: 60.052g/mol-:
95.0g * (1mol / 60.052g) = 1.58 moles
Heat released:
1.58 moles * (-11.72kJ/mol) =
-18.54kJ of energy would be releasedThe volume of a 1.00-mole sample of an ideal gas will decrease when the
1.
pressure decreases and the temperature decreases
2.
pressure decreases and the temperature increases
3.
pressure increases and the temperature decreases
4.
pressure increases and the temperature increases
Answer:
The correct option is (3).
Explanation:
The ideal gas equation is given by :
[tex]PV=nRT\\\\V=\dfrac{nRT}{P}[/tex]
The pressure of ideal gas is directly proportional to temperature and inversely proportional to its volume.
We can say that the volume of a 1.00-mole sample of an ideal gas will decrease when the pressure increases and the temperature decreases.
The volume of the idea gas decrease when pressure increases and the temperature decreases. Thus option C is correct.
The ideal gas equation can be given as:
PV = nRT
The equation in terms of pressure and temperature when n=1 can be written as:
Volume = [tex]\rm \dfrac{RT}{P}[/tex]
Accordingly, the volume has been directly proportional to the temperature and has been inversely proportional to the pressure.
Thus, with the decrease in volume, there has been an increase in pressure and a decrease in temperature.
Thus, option C is correct.
For more information about the ideal gas, refer to the link:
https://brainly.com/question/8711877
How many oxygen atoms are in 3.30 g of quartz?
Answer:
3.30 gSiO2 / 60.085g SiO2 x 2 mol 0 / 1 mol SiO2 x (6.022*1023 ) = 6.61*1022 O atoms
Explanation:
why is nitrogen used for storage of semen in artificial insemination
Answer:
Explanation:
Nitrogen is use to store semen for artificial insemination because if it's inert characteristics which it help to maintain the semen inertness and also it maintain the low temperature of the semen which is good for it's quality.
Nitrogen also help to prevent it's biological deterioration thereby maintaining it's viability and effectiveness.
Question 2/8
From left to right across the second period of the periodic table,
Answer:
HE
Explanation:
HE is a noble gas
Comprehension Questions:
1. Changing location
change an
object's mass. (does/does not)
O
does
O does not
Answer:
It does not change and object's mass
Most synesthetes are:
a.
women
b. men
C. children
d. artists
Please select the best answer from the choices provided
Ο Α
B.
С
D
Answer:
d
Explanation:
its artist school kills artists
Answer:
Hello There!!
Explanation:
The answer is D.artists because they trigger colors.
hope this helps,have a great day!!
~Pinky~
What is matter?
O A. Anything that can be seen.
O B. Anything that can be treasured
O C. Anything that takes up space and has mass
B. Anything that has
energy and motion
Answer:
Anything that takes up space and has mass
HELPPPP PLZZZZ
“Our world is like a web made up of many strands, all connected together. Break one connection, and the whole web may change.”
What might the author be trying to communicate about biodiversity in these sentences
Answer:
hope yall have agreat day
Explanation
The atmospheric pressure at 1000 m altitude is 0.868 atm.
What is this pressure in Pascals?
Pa
Answer:0.868
Explanation:
Answer: 87950.1 Pascals