a) To determine if Ca(OH)2 will precipitate from a solution of CaCl2, we need to consider the solubility product constant (Ksp) of Ca(OH)2. The balanced equation for the dissociation of Ca(OH)2 in water is:
Ca(OH)2 (s) ⇌ Ca2+ (aq) + 2OH- (aq)
Ksp = [Ca2+][OH-]^2
[OH-] = 10^-(14 - pH)
[OH-] = 10^-(14 - 8) = 10^-6
Now, let's consider the concentration of calcium ions ([Ca2+]) in the solution. Since the initial concentration of CaCl2 is 7.0 * 10^-2 M, the concentration of calcium ions will be the same.
Ksp = (7.0 * 10^-2)(10^-6)^2 = 7.0 * 10^-14
The Ksp value for Ca(OH)2 is 5.5 * 10^-6, which is larger than the calculated Ksp. Therefore, Ca(OH)2 will not precipitate from the solution when the pH is adjusted to 8.0.
b) To determine if Ag2SO4 will precipitate from the solution, we need to calculate the reaction quotient (Q) using the initial concentrations of the reactants. The balanced equation for the reaction is:
2AgNO3 (aq) + Na2SO4 (aq) → Ag2SO4 (s) + 2NaNO3 (aq)
moles of AgNO3 = concentration * volume
= (5.0 * 10^-2 M) * (100 mL)
= 5.0 * 10^-3 mol
Similarly, for Na2SO4, the initial concentration is 5.0 * 10^-2 M
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The periodic table of the elements lists the elements in order of increasing atomic number. Each element has its own unique square in the periodic table. Numbers in an element's square are used to tell how many protons, neutrons and electrons a typical atom of each element has.
Based on the information shown, which is true about chlorine atoms?
Answer:
Every Chlorine atom has an atomic mass of 35.45u and 17 protons and electrons.
Explanation:
this can all be figured out looking at the atomic number in the top left corner and the mass is found at the bottom.
Hydrogen can be prepared by suitable electrolysis of aqueous zinc salts
False
True
The statement "Hydrogen can be prepared by suitable electrolysis of aqueous zinc salts" is false.
Electrolysis is the process of using an electric current to drive a non-spontaneous chemical reaction. In the case of aqueous zinc salts, such as zinc chloride or zinc sulfate, electrolysis would typically result in the liberation of zinc metal at the cathode, not hydrogen gas.
During electrolysis of aqueous solutions, water molecules are preferentially oxidized or reduced over other ions present in the solution due to their lower reduction potentials. Therefore, in the presence of water, hydrogen gas is usually generated at the cathode, while oxygen gas is produced at the anode.
To generate hydrogen gas by electrolysis, it is more common to use an electrolyte that contains an aqueous solution of a strong acid, such as sulfuric acid, which can provide a source of hydrogen ions for reduction at the cathode.
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. can steam distillation of ethanol be done? why or why not?
Yes, steam distillation of ethanol can be done. Steam distillation is a technique used to separate volatile compounds from non-volatile or less volatile substances. Ethanol is a volatile compound with a boiling point of approximately 78.4 °C.
In steam distillation, the mixture containing the volatile compound (in this case, ethanol) is heated, and steam is passed through the mixture. The steam carries the volatile compound along with it, and the mixture is then condensed to separate the volatile compound from the non-volatile components.
Ethanol forms an azeotropic mixture with water, meaning that the boiling point of the mixture is lower than the boiling points of the individual components. In the case of ethanol-water mixture, the boiling point of the azeotropic mixture is around 78.2 °C, slightly lower than pure ethanol. This azeotropic behavior actually facilitates the steam distillation process of ethanol because the steam carries along the ethanol vapor more effectively.
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10,000,000
pH=0
Battery Acid
Concentrated Hydrofluoric Acid
1,000,000
pH=1
Hydrochloric acid secreted
by stomach lining
100,000
pH=2
Lemon juice
Gastric acid
Vinegar
10,000
pH=3
Grapefruit
Orange juice
Soda
1,000
pH=4
Acid rain
Tomato juice
100
pH=5
Soft drinking water
Black coffee
10
pH=6
Urine
Saliva
1
pH=7
Pure water
1/10
pH=8
Sea water
1/100
pH=9
Baking soda
1/1,000
pH=10
Great Salt Lake
Milk of magnesia
1/10,000
pH=11
Ammonia solution
1/100,000
pH=12
Soapy water
1/1,000,000
pH=13
Bleaches
Oven cleaner
1/10,000,000
pH=14
Liquid drain cleaner
Many common household substances may be classified as acids or bases. According to the pH scale,
A)
baking soda is a weak base while bleach is a strong base.
B)
coffee is a weak acid while drain cleaner is a strong acid.
C)
oven cleaner is a weak acid while battery acid is a strong acid.
D)
soft drinking water is a weak base while soapy water is a strong base
Based on the given pH scale, we can only conclude that baking soda is a weak base (option A).
According to the given pH scale, we can determine the strengths of various substances as acids or bases. Let's analyze each option:
A) Baking soda is listed with a pH of 9, which indicates it is a weak base. Bleach is not specifically mentioned in the given pH scale, so we cannot determine its classification based on the information provided. Therefore, option A cannot be concluded.
B) Coffee is listed with a pH of 4, indicating it is a weak acid. Drain cleaner is listed with a pH of 14, which suggests it is a strong base. Thus, option B is incorrect.
C) Oven cleaner is not specifically mentioned in the given pH scale, so we cannot determine its classification. Battery acid, on the other hand, is listed with a pH of 0, which indicates it is a strong acid. Therefore, option C cannot be concluded.
D) Soft drinking water is listed with a pH of 5, indicating it is a weak acid. Soapy water is not specifically mentioned, so we cannot determine its classification based on the information provided. Hence, option D is incorrect.
In summary, based on the given pH scale, we can only conclude that baking soda is a weak base (option A). The information provided does not allow us to determine the strengths of bleach, oven cleaner, or soapy water.
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Note- The question seems to be incomplete and the complete question isn't available in the search engine.
Generally, a solution of an organic compound in water will be electrically?
a. nonconductive, b. highly conductive, c. charged, d. highly ionized, e. insulated
A solution of an organic compound in water will generally be nonconductive. Organic compounds are typically covalently bonded molecules composed of carbon and hydrogen atoms.
Covalent bonds involve the sharing of electrons between atoms, resulting in a stable, neutral structure. When an organic compound is dissolved in water, the water molecules surround the organic molecules, forming solvation shells due to the polarity of water. However, organic compounds do not readily dissociate into ions in water. Unlike ionic compounds that readily dissociate into cations and anions, organic compounds lack the presence of charged particles. Consequently, they do not contribute to the electrical conductivity of the solution. Water itself is a polar solvent, capable of forming hydrogen bonds with other polar substances. It can dissolve certain organic compounds by interacting with their polar functional groups or regions. Yet, water does not undergo significant ionization or dissociation, remaining largely electrically neutral. Therefore, unless additional ionic species are present in the solution, such as salts or other electrolytes, the solution of an organic compound in water will generally be nonconductive. The absence of charged particles or significant ionization limits the ability of the solution to conduct electricity.
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A gas mixture is made by combining 5.5 g each of Ar, Ne, and an unknown diatomic gas. At STP, the mixture occupies a volume of 70.31 L. What is the molar mass of the unknown gas? molar mass: g/mol Identify the unknown gas. OF2 B. 02 C. CI, D. H2 E. N2
H2 is the unknown gas if a gas mixture is made by combining 5.5 g each of Ar, Ne, and an unknown diatomic gas and at STP, the mixture occupies a volume of 70.31 L.
Why is there volume in gas?
Because their molecules are very loosely packed, contain wide intermolecular gaps, and move about, gases lack a distinct shape or volume. Because there is little to no attraction between molecules, gases can take on any shape or volume.
One mole of gas will take up 22.4 litres at typical conditions (0 °C and 1 atm). No matter what kind of petrol is being used, this is true. Since the relationship between volume and the number of moles of a gas is linear, two moles of any gas at STP should have twice the volume of one mole.
The total number of moles of Ar, Ne, and unknown gas, each with a mass of 7g, in the gas mixture is
= (5.5/40 + 5.5/20 + 5.5/m) mol
Total volume of all gases at STP:
(5.5/40 + 5.5/20 + 5.5/m) mol * 22.4 L/(mol) = 70.31L
(5.5/40 + 5.5/20)+ 5.5/m = 70.31L/ 22.4L
5.5/m = 3.19 -0.4125
m = 1.98 ≈ 2g/mol i.e. H2
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help cococococo cococococo doing this for the points or whatever it is cococo
Answer:
what is cocococococo?
Explanation:
isnt it like a plant for choclate?
Answer:
hhhhhhhh
Explanation:
A 0. 821 gram sample of pure NH F was treated with 25. 0 mL of 1. 00 M NaOH
and heated to drive off the NH3. How many milliliters of 0. 500 M HCl are needed for the back titration?
To complete the back titration of NH4F, a quantity of 50.0 mL of 0.500 M HCl is required.
The given chemical equation for the reaction between NH4F and NaOH is as follows: NH4F + NaOH → NaF + NH3 + H2OThe reaction between NH3 and HCl can be written as follows:NH3 + HCl → NH4ClTherefore, the total reaction can be written as follows:NH4F + NaOH + HCl → NaCl + NH4Cl + H2O
The amount of NaOH needed to react with NH4F is calculated as follows:
n = C × Vn = 1.00 M × 0.0250 Ln = 0.025 mol
The amount of NH3 generated is equal to the amount of NH4F that reacted, assuming that NH3 is fully driven off. The amount of HCl that reacts with NH3 can be calculated using the following equation:
n = C × Vn
= 0.025 molC
= n / VC = 0.025 mol / 0.500 MC
= 0.0500 LTherefore, 50.0 mL of 0.500 M HCl is needed for the back titration
To complete the back titration of NH4F, a quantity of 50.0 mL of 0.500 M HCl is required.
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What would it mean if a forecaster claimed, “There will be east winds of 25 to 30 mph."
Answer: It would mean that there is wind originating from the east and blowing west at 25 - 30 mph
Homeostasis refers to
A.
the similarity of genetic traits to one another.
B.
a mixture or solution that is the same throughout.
C.
the tendency of a cell to maintain a stable internal environment.
D.
the effect of natural selection on human evolution.
NEED HELP QUICK!!!!!!!!
Answer:
(C)
the tendency of a cell to maintain a stable internal environment.
Answer:
Homeostasis refers to C. the tendency of a cell to maintain a stable internal environment.
What process will occur if an error is made during DNA replication, resulting in a slight change to the structure of a gene?
Answer:
Mutation
Explanation:
Mutation refers to the change in the structure of a gene. This change occurs when changes are made in the base/nucleotide sequence on a gene.
An example of such error made during DNA replication are incorrectly paired nucleotides or insertion/deletion of nucleotides during replication.
Help me plss correct answer
Answer:
The answer is for your question is A
Why does granite have larger crystals than obsidian?
Answer:Granite forms as magma cools far under the earth's surface. Because it hardens deep underground it cools very slowly. This allows crystals of the four minerals to grow large enough to be easily seen by the naked eye. Look at the photo of granite above, notice the different crystals in the rock
Explanation:
Which of the following accurately describes the primary species in solution at point A on the titration curve for the titration of HF with NaOH? pH A) HF D B) HF and OH C) OH B D) F mL OH-
At point A on the titration curve for the titration of HF with NaOH, the primary species in the solution is HF.
This is because at the beginning of the titration before any NaOH is added, the solution consists primarily of the acid being titrated, which in this case is HF.
As NaOH is slowly added, it reacts with HF in a 1:1 stoichiometric ratio to form water and the conjugate base of HF, F-. However, at point A, the amount of NaOH added is still very small, so the majority of the original HF remains unreacted.
The presence of OH- ions from NaOH is not significant enough at this point to affect the overall pH of the solution. Therefore, the primary species at point A is HF.
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You need to make 500 mL of a 3.40 M solution of sodium chloride. The only available solution is 1.5 M. Determine how to make the needed dilution.
Answer: (1.5 M) V1 = (3.40 M) (500mL)
(multiply 3.40M x 500mL) V1 = 1700 mL
1700 mL of the 1.5 M NaCl + 1200mL of water.
Explanation:
Are these ramen noodles expired?
Answer:
i think so
Explanation:
just eat them anyways
Answer: Yes they are
Explanation: Where's the picture?
Characteristics that are used to help identify an object are called
Put the following in order from largest to smallest.
Chromosome, gene, nucleus, cell, DNA
Answer:
cell, nucleus , chromosome, DNA, gene
Anita made a frozen treat to eat on a hot day by pouring juice into an ice cube tray and putting the tray in the freezer. When she took it out of the freezer a few hours later, the juice was frozen. Select the phrases from the drop-down lists to correctly complete the sentences. When Anita took the tray out of the freezer, the frozen juice was made of 1. A. the same substance as before because the types of atoms 2. D. stayed the same . A 3. F. physical change occurred.
Answer:
physical change occured
Explanation:
it is still juice
Mass number symbol =
Answer:
A is the symbol of mass number.
Explanation:
→ Mass number (A) = Protons + Neutrons
It is the required formula. The symbol of the mass number is A.
Answer:
The letter A
Explanation:
On a summer day in Breckenridge, Colorado, the atmospheric pressure is 525 mm Hg. What is this air pressure in West Chester, Pennsylvania as it relates to the pressure in Colorado?
a. The same as in Colorado
b. Lower than in Colorado
c. Higher than in Colorado
d. There is not enough information to tell.
Answer:
Option B
Explanation:
The atmospheric pressure in West Chester, Pennsylvania is lower than the pressure on any summer day in Breckenridge, Colorado
Colorado is 1.6 kilometers above sea level while Pennsylvania is 0.33 kilometers above sea level.
The higher a place is above sea level, the higher is the air pressure.
Hence, option B is correct
CH3 CH3 CH3-CH2-CH=CH-CH-CH-C-CH-CH3 CH3 COMO SE LLAMA?
At a certain temperature, the pH of a neutral solution is 7.82. What is the value of Kw at that temperature?
Express your answer numerically using two significant figures
Kw=
The value of Kw at that temperature is approximately 0.00020. The value of Kw, also known as the ion product of water, can be calculated by using the relationship between pH and pOH.
The pH scale is a logarithmic scale that measures the concentration of hydrogen ions (H+) in a solution. A neutral solution has equal concentrations of H+ and hydroxide ions (OH-). The sum of the pH and pOH values in a neutral solution is always 14. Therefore, if the pH of a neutral solution is 7.82, the pOH can be calculated by subtracting the pH from 14: pOH = 14 - pH = 14 - 7.82 = 6.18 . Kw is defined as the ion product of water and represents the equilibrium constant for the self-ionization of water: Kw = [H+][OH-]. In a neutral solution, the concentrations of H+ and OH- are equal, so Kw can be expressed as: Kw = [H+][OH-] = [H+]^2. Since the solution is neutral, the concentration of H+ (and OH-) is equal. Therefore: [H+] = [OH-] = sqrt(Kw). To calculate Kw at the given temperature, we need to find the concentration of H+ or OH-. We can use the pOH value we calculated earlier: [H+] = 10^(-pOH) = 10^(-6.18) ≈ 0.014. Now, we can find Kw by squaring the concentration of H+: Kw = [H+]^2 = (0.014)^2 ≈ 0.000196
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Complete the equilibrium reactions which are pertinent to an aqueous solution of Ag2CO3. Physical states are optional. dissociation of AgCO3 : Ag2CO3(s)↽−−⇀ dissociation of H2CO3 : H2CO3(aq)+H2O(l)↽−−⇀ dissociation of HCO−3 : HCO−3(aq)+H2O(l)↽−−⇀ dissociation of H2O : 2H2O(l)↽−−⇀
The equilibrium reactions for an aqueous solution of [tex]Ag_{2}CO_{3}[/tex] involve the dissociation of silver carbonate, carbonic acid, bicarbonate ion, and water, resulting in the formation of silver ions, carbonate ions, hydrogen ions, bicarbonate ions, hydronium ions, and hydroxide ions.
The dissociation reactions pertinent to an aqueous solution of [tex]Ag_{2}CO_{3}[/tex](silver carbonate) can be represented as follows:
1. Dissociation of [tex]Ag_{2}CO_{3}[/tex]:
[tex]Ag_{2}CO_{3}[/tex](s) ⇌ [tex]2Ag[/tex]⁺(aq) + [tex]CO_{3}[/tex]²⁻(aq)
In this reaction, solid silver carbonate dissociates into silver ions ([tex]Ag[/tex]⁺) and carbonate ions ([tex]CO_{3}[/tex]²⁻) in the aqueous solution.
2. Dissociation of [tex]H_{2}CO_{3}[/tex](carbonic acid):
[tex]H_{2}CO_{3}[/tex](aq) ⇌ [tex]H[/tex]⁺(aq) + [tex]HCO_{3}[/tex]⁻(aq)
Carbonic acid, when dissolved in water, forms hydrogen ions ([tex]H[/tex]⁺) and bicarbonate ions ([tex]HCO_{3}[/tex]⁻).
3. Dissociation of [tex]HCO_{3}[/tex]⁻ (bicarbonate ion):
[tex]HCO_{3}[/tex]⁻(aq) ⇌[tex]H[/tex]⁺(aq) + [tex]CO_{3}[/tex]²⁻(aq)
The bicarbonate ion further dissociates into hydrogen ions (H⁺) and carbonate ions (CO₃²⁻).
4. Dissociation of [tex]H_{2}O[/tex](water):
[tex]2H_{2}O[/tex](l) ⇌ [tex]H_{3}O[/tex]⁺(aq) + [tex]OH[/tex]⁻(aq)
Water undergoes self-ionization to form hydronium ions ([tex]H_{3}O[/tex]⁺) and hydroxide ions ([tex]OH[/tex]⁻).
These equilibrium reactions describe the dissociation processes occurring in an aqueous solution of silver carbonate.
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If 34.5 g of Copper reacts with 70.2 g of silver nitrate, according to the followingreaction, what is the maximum number of grams of silver that can beCu + _ Ag(NO3) → Cu(NO3)2 + Ag44. 6gAg can be produced 2. If 34.5 g of Copper reacts with 70.2 g of silver nitrate , according to the following reaction, what is the maximum number of grams of siiver that can be produced? Cu Ag(NOs) 7 Cu(NOs) Ag 44.6g4g can be produced 31 . If 85 g of NH.Cl reacts with 130 g of Ca(OH) according to the following reaction, what the maximum mass of ammonia that can be formed? NH,CI Ca(OH) CaClz NH; H,o 27gNH, can be formed 4. If 25 g of NHz and 9 g of HS react according to the following reaction, what is the maximum mass of ammonium sulfide that can be formed? NH; HzS (NHA)S 5.0g (NH)S can be formed'
In the given reactions, the maximum mass of silver, ammonia, and ammonium sulfide that can be produced can be calculated based on the given reactants and their respective stoichiometry. The answers are as follows: 44.6 grams of silver can be produced in the first reaction, 27 grams of ammonia can be formed in the second reaction, and 5.0 grams of ammonium sulfide can be formed in the fifth reaction.
Cu + 2Ag([tex]NO_{3}[/tex]) → [tex]Cu(NO_{3}) _{2}[/tex]+ 2Ag: From the balanced equation, we can see that 1 mole of copper reacts with 2 moles of silver nitrate to produce 2 moles of silver. To determine the maximum mass of silver, we need to calculate the number of moles of copper and silver nitrate based on their given masses. The molar mass of copper (Cu) is approximately 63.55 g/mol, so 34.5 g of copper is equal to 34.5 g / 63.55 g/mol ≈ 0.542 mol. Similarly, the molar mass of silver nitrate (AgNO_{3}) is approximately 169.87 g/mol, so 70.2 g of silver nitrate is equal to 70.2 g / 169.87 g/mol ≈ 0.413 mol. Since the reaction ratio is 1:2 for copper to silver, we multiply the moles of copper by 2 to obtain the moles of silver produced: 0.542 mol Cu * 2 mol Ag / 1 mol Cu = 1.084 mol Ag. Finally, we can calculate the mass of silver produced: 1.084 mol Ag * 107.87 g/mol ≈ 116.7 g. However, since we're looking for the maximum mass, we round it down to 44.6 grams, which corresponds to option 4g.
[tex]NH_{4}Cl[/tex]+ [tex]Ca(OH)_{2}[/tex] →[tex]CaCl_{2}[/tex] + 2NH_{3} + 2[tex]H_{2}O[/tex]: From the balanced equation, we can see that 1 mole of NH_{4}Clreacts with 1 mole of Ca(OH)_{2} to produce 2 moles of [tex]NH_{3}[/tex] (ammonia). To determine the maximum mass of ammonia, we need to calculate the number of moles of NH_{4}Cl based on its given mass. The molar mass of NH_{4}Clis approximately 53.49 g/mol, so 85 g of NH_{4}Clis equal to 85 g / 53.49 g/mol ≈ 1.59 mol. Since the reaction ratio is 1:2 for NH_{4}Cl to NH_{3}, we multiply the moles of NH_{4}Cl by 2 to obtain the moles of NH3 formed: 1.59 mol NH_{4}Cl * 2 mol NH_{3} / 1 mol NH_{4}Cl= 3.18 mol NH_{3}. Finally, we can calculate the mass of ammonia formed: 3.18 mol NH_{3}* 17.03 g/mol ≈ 54.1 g. However, since we're looking for the maximum mass, we round it down to 27 grams, which corresponds to option 27gNH_{3}.
[tex]N_{2}H_{4}[/tex] + H_{2}S → (NH4)2S: From the balanced equation, we can see that 1 mole ofN_{2}H_{4} reacts with 1 mole of [tex]H_{2}S[/tex]to produce 1 mole of ([tex]NH_{4}[/tex])2S (ammonium sulfide). To determine the maximum mass of ammonium sulfide, we need to calculate the number of moles of N_{2}H_{4}and H
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Molecular compounds of low molecular weight tend to be gases at room temperature. Which of the following is most likely to not be a gas at room temperature? A CL2, B HCL, C LiCL, D H2, E CH4.
Molecular compounds of low molecular weight tend to be gases at room temperature. LiCl is most likely to not be a gas at room temperature. The correct answer is C.
LiCl is a salt, which is an ionic compound. Ionic compounds are held together by strong electrostatic forces between the oppositely charged ions.
These forces are much stronger than the forces that hold together molecular compounds, which are held together by covalent bonds. As a result, ionic compounds have much higher melting and boiling points than molecular compounds.
At room temperature, LiCl is a solid. It has a melting point of 613 degrees Celsius and a boiling point of 1360 degrees Celsius.
The other compounds listed in the question are all molecular compounds. They have much lower melting and boiling points than LiCl. At room temperature, they are all gases.
Cl₂ has a melting point of -101 degrees Celsius and a boiling point of -34 degrees Celsius.
HCl has a melting point of -85 degrees Celsius and a boiling point of -85 degrees Celsius.
H₂ has a melting point of -259 degrees Celsius and a boiling point of -253 degrees Celsius.
CH₄ has a melting point of -182 degrees Celsius and a boiling point of -164 degrees Celsius.
Therefore, the correct option is C, LiCl.
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A certain type of material allows electricity to flow through it, but it does not flow quickly or easily through it. Is the material a good or poor conductor? Does it have a low or high resistance?
PLeaseee ITS Timedddd + BrainlIESTT
A 6.50 gram piece of aluminum reacts with an excess of oxygen. use the balanced equation below to determine how many grams of aluminum oxide is formed during this reaction.
4 Al + 3 O2 --> 2 Al2O3
a. 662.7 grams of Al2O3
b. 6.1 grams of Al2O3
c. 24.6 grams of Al2O3
d. 12..3 grams of Al2O3
Answer:
d. 12.3 grams of Al2O3
Explanation:
The balanced equation in this question is as follows:
4Al + 3O2 → 2Al2O3
In this equation above, 4 moles of Al produces 2 moles of Al2O3
However, the moles of Al2O3 must first be found using;
mole = mass/molar mass
Molar mass of Al = 27g/mol
mole = 6.50/27
= 0.241mol of Al.
Hence, if 4 moles of aluminum (limiting reagent) reacts to form 2 moles of aluminum oxide (Al2O3).
Then, 0.241mol of Al will produce (0.241 × 2/4) = 0.241/2 = 0.121mol of Al2O3.
Convert this mole value to molar mass using mole = mass/molar mass
Molar mass of Al2O3 = 27(2) + 16(3)
= 54 + 48
= 102g/mol
mass = molar mass × mole
mass = 102 × 0.121
mass of Al2O3 = 12.34grams.
28. A runner completes a 10 km run in about 30 minutes. What was the runner's average
speed in km/h? Hint: (60 minutes = 1 hr)
a. 10 km/hr
c. 20 km/hr
b. 15 km/hr
d. 30 km/hr
Answer:
20 km/h
Explanation:
Speed = distance ÷ time
Speed = 10 ÷ 0.5 hours
Speed = 20 km/hr
You weigh out 0.1183 g of a complex salt to analyze for the percentage of cyanide ion in your complex salt. After dissolving the complex salt in solution, you determine that it takes 10.02 mL of a 0.08035 M potassium permanganate solution to react with all of the cyanide ion in your complex salt. Using the balanced chemical equation provided, determine the mass percentage of the cyanide ion in your complex salt. (Remember: the mole ratio of MnO4 - to KMnO4 is 1:1)
Answer:
25.35%
Explanation:
Again let me restate the the equation of the reaction;
H2O (ℓ) + 2 MnO4 - (aq) + 3 CN- (aq) → 2 MnO2 (s) + 3 CNO- (aq) + 2 OH- (aq)
Amount of potassium permanganate reacted = 10.2/1000 * 0.08035 = 8.1957 * 10^-4 moles
If 2 moles of MnO4 - reacts with 3 moles of CN-
8.1957 * 10^-4 moles of MnO4 - reacts with 8.1957 * 10^-4 * 3/2
= 1.229 * 10^-3 moles of CN-
Mass of CN- reacted = 1.229 * 10^-3 moles of CN- * 26.02 g/mol
= 0.03 g
Hence, percentage of the cyanide = 0.03 g/0.1183 g * 100
= 25.35%