Question 1

How many moles are in 7.8 g of acetamide,CH3CONH2?

Accepted Answer

Question 2

Which one of the following is not an empirical formula?

Accepted Answer

A) CHO 
B) CH2O 
C) C2H4O 
D) C2H4O2 
A) CHO 
B) CH2O 
C) C2H4O 
D) C2H4O2

Question 3

Which of the following has the smallest mass?

Accepted Answer

A) 3)50 × 1023 molecules of I2 
B) 85.0 g of Cl2 
C) 2)50 mol of F2 
D) 0)050 kg of Br2 
A) 3)50 × 1023 molecules of I2 
B) 85.0 g of Cl2 
C) 2)50 mol of F2 
D) 0)050 kg of Br2

Question 4

If the percent yield for the following reaction is 65.0%,how many grams of KClO3 are needed to produce 32.0 g of O2?
2 KClO3(s)→ 2 KCl(s)+ 3 O2(g)

Accepted Answer

A) 53.1 g 
B) 81.7 g 
C) 126 g 
D) 283 g 
A) 53.1 g 
B) 81.7 g 
C) 126 g 
D) 283 g

Question 5

What is the molar mass of Co(NO3)2?

Accepted Answer

A) 90 g/mol 
B) 121 g/mol 
C) 152 g/mol 
D) 183 g/mol 
A) 90 g/mol 
B) 121 g/mol 
C) 152 g/mol 
D) 183 g/mol

Question 6

What is the mass of 0.500 mol of dichlorodifluoro methane,C Cl2F2?

Accepted Answer

A) 4)14 × 10-3 g 
B) 60.5 g 
C) 121 g 
D) 242 g 
A) 4)14 × 10-3 g 
B) 60.5 g 
C) 121 g 
D) 242 g

Question 7

The density of ethanol,C2H5OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 10.0 g of CO2 according to the following chemical equation?
C2H5OH(l)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(l)

Accepted Answer

A) 4)12 mL 
B) 6)63 mL 
C) 13.2 mL 
D) 26.5 mL 
A) 4)12 mL 
B) 6)63 mL 
C) 13.2 mL 
D) 26.5 mL

Question 8

Ozone is unstable,decomposing to dioxygen,as shown in the balanced equation
2 O3 → 3 O2.
In this reaction,how many grams of dioxygen can be formed from the decomposition of 96 grams of ozone?

Accepted Answer

Question 9

In the combustion analysis of an unknown compound containing only carbon,hydrogen,and oxygen,the grams of oxygen are found from the grams of

Accepted Answer

A) CO2 only. 
B) H2O only. 
C) CO2 and H2O only. 
D) CO2,H2O and unknown compound. 
A) CO2 only. 
B) H2O only. 
C) CO2 and H2O only. 
D) CO2,H2O and unknown compound.

Question 10

What is the mass of 8.50 x 1022 molecules of NH3?

Accepted Answer

A) 0)00 829 g 
B) 0)417 g 
C) 2)40 g 
D) 121 g 
A) 0)00 829 g 
B) 0)417 g 
C) 2)40 g 
D) 121 g

Question 11

How many moles of CuO can be produced from 0.900 mol of Cu2O in the following reaction?
2 Cu2O(s)+ O2(g)→ 4 CuO(s)

Accepted Answer

A) 0)450 mol 
B) 0)900 mol 
C) 1)80 mol 
D) 3)60 mol 
A) 0)450 mol 
B) 0)900 mol 
C) 1)80 mol 
D) 3)60 mol

Question 12

When 5.00 × 1022 molecules of ammonia react with 4.00 × 1022 molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced?
4 NH3(g)+ 3 O2(g)→ 2 N2(g)+ 6 H2O(g)

Accepted Answer

A) 1)16 g 
B) 1)24 g 
C) 2)79 g 
D) 4)65 g 
A) 1)16 g 
B) 1)24 g 
C) 2)79 g 
D) 4)65 g

Question 13

When iron(III)oxide reacts with hydrochloric acid,iron(III)chloride and water are formed.How many grams of iron(III)chloride are formed from 10.0 g of iron(III)oxide and 10.0 g of hydrochloric acid?

Accepted Answer

A) 11.1 g 
B) 14.8 g 
C) 20.3 g 
D) 35.1 g 
A) 11.1 g 
B) 14.8 g 
C) 20.3 g 
D) 35.1 g

Question 14

What is the mass of 8.50 × 1022 molecules of NH3?

Accepted Answer

A) 0)00830 g 
B) 0)417 g 
C) 2)40 g 
D) 120 g 
A) 0)00830 g 
B) 0)417 g 
C) 2)40 g 
D) 120 g

Question 15

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation:
2 S(s)+ 3 O2(g)+ 4 NaOH(aq)→ 2 Na2SO4(aq)+ 2 H2O(l)

Accepted Answer

A) S(s) 
B) O2(g) 
C) NaOH (aq) 
D) None of these substances is the limiting reactant. 
A) S(s) 
B) O2(g) 
C) NaOH (aq) 
D) None of these substances is the limiting reactant.

Question 16

A student dissolved 3.00 g of Co(NO3)2 in enough water to make 100.mL of stock solution.He took 4.00 mL of the solution then diluted it with water to give 275 mL of a final solution.How many grams of NO3- ion are there in the final solution?

Accepted Answer

A) 0)0148 g 
B) 0)0296 g 
C) 0)0407 g 
D) 0)0813 g 
A) 0)0148 g 
B) 0)0296 g 
C) 0)0407 g 
D) 0)0813 g

Question 17

Box (1)represents 1.0 mL of a solution of particles at a given concentration.  
-Which of the boxes (2)-(5)represents 1.0 mL of the solution that results after (1)has been diluted by adding enough solvent to make 5.0 mL of solution?

Accepted Answer

A) box (2) 
B) box (3) 
C) box (4) 
D) box (5) 
A) box (2) 
B) box (3) 
C) box (4) 
D) box (5)

Question 18

Reaction of A (unshaded spheres)with B2 (shaded spheres)is shown schematically in the following diagram.Which equation best describes the stoichiometry of the reaction?

Accepted Answer

A) A2 + 2 B → A2B2 
B) 8 A + 4 B2 → 4 A2B2 
C) 2 A + B2 → A2B2 
D) 4 A + 4 B2 → 4 A2B2 
A) A2 + 2 B → A2B2 
B) 8 A + 4 B2 → 4 A2B2 
C) 2 A + B2 → A2B2 
D) 4 A + 4 B2 → 4 A2B2

Question 19

The fundamental SI unit for measuring matter is the ________.

Accepted Answer

The answer of The fundamental SI unit for measuring matter...

Question 20

Glucose,C6H1206,can be represented by the molecular model shown below.If 1.00 mol of glucose is submitted to combustion analysis,how many moles of CO2 and how many moles of H2O would be formed?

Accepted Answer

A) 1)00 mol CO2 and 2.00 mol H2O 
B) 6)00 mol CO2 and 6.00 mol H2O 
C) 6)00 mol CO2 and 12.0 mol H2O 
D) 12.0 mol CO2 and 12.0 mol H2O 
A) 1)00 mol CO2 and 2.00 mol H2O 
B) 6)00 mol CO2 and 6.00 mol H2O 
C) 6)00 mol CO2 and 12.0 mol H2O 
D) 12.0 mol CO2 and 12.0 mol H2O

Exam 3: Formulas, equations, and Moles

How many moles are in 7.8 g of acetamide,CH3CONH2?

Which one of the following is not an empirical formula?

Which of the following has the smallest mass?

If the percent yield for the following reaction is 65.0%,how many grams of KClO3 are needed to produce 32.0 g of O2? 2 KClO3(s)→ 2 KCl(s)+ 3 O2(g)

What is the molar mass of Co(NO3)2?

What is the mass of 0.500 mol of dichlorodifluoro methane,C Cl2F2?

The density of ethanol,C2H5OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 10.0 g of CO2 according to the following chemical equation? C2H5OH(l)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(l)

Ozone is unstable,decomposing to dioxygen,as shown in the balanced equation 2 O3 → 3 O2. In this reaction,how many grams of dioxygen can be formed from the decomposition of 96 grams of ozone?

In the combustion analysis of an unknown compound containing only carbon,hydrogen,and oxygen,the grams of oxygen are found from the grams of

What is the mass of 8.50 x 1022 molecules of NH3?

How many moles of CuO can be produced from 0.900 mol of Cu2O in the following reaction? 2 Cu2O(s)+ O2(g)→ 4 CuO(s)

When 5.00 × 1022 molecules of ammonia react with 4.00 × 1022 molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH3(g)+ 3 O2(g)→ 2 N2(g)+ 6 H2O(g)

When iron(III)oxide reacts with hydrochloric acid,iron(III)chloride and water are formed.How many grams of iron(III)chloride are formed from 10.0 g of iron(III)oxide and 10.0 g of hydrochloric acid?

What is the mass of 8.50 × 1022 molecules of NH3?

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s)+ 3 O2(g)+ 4 NaOH(aq)→ 2 Na2SO4(aq)+ 2 H2O(l)

A student dissolved 3.00 g of Co(NO3)2 in enough water to make 100.mL of stock solution.He took 4.00 mL of the solution then diluted it with water to give 275 mL of a final solution.How many grams of NO3- ion are there in the final solution?

Box (1)represents 1.0 mL of a solution of particles at a given concentration. -Which of the boxes (2)-(5)represents 1.0 mL of the solution that results after (1)has been diluted by adding enough solvent to make 5.0 mL of solution?

Reaction of A (unshaded spheres)with B2 (shaded spheres)is shown schematically in the following diagram.Which equation best describes the stoichiometry of the reaction?

The fundamental SI unit for measuring matter is the ________.

Glucose,C6H1206,can be represented by the molecular model shown below.If 1.00 mol of glucose is submitted to combustion analysis,how many moles of CO2 and how many moles of H2O would be formed?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

How many moles are in 7.8 g of acetamide,CH₃CONH₂?

If the percent yield for the following reaction is 65.0%,how many grams of KClO₃ are needed to produce 32.0 g of O₂? 2 KClO₃(s)→ 2 KCl(s)+ 3 O₂(g)

What is the molar mass of Co(NO₃)₂?

What is the mass of 0.500 mol of dichlorodifluoro methane,C Cl₂F₂?

The density of ethanol,C₂H₅OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 10.0 g of CO₂ according to the following chemical equation? C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(l)

Ozone is unstable,decomposing to dioxygen,as shown in the balanced equation 2 O₃ → 3 O₂. In this reaction,how many grams of dioxygen can be formed from the decomposition of 96 grams of ozone?

What is the mass of 8.50 x 10²² molecules of NH₃?

How many moles of CuO can be produced from 0.900 mol of Cu₂O in the following reaction? 2 Cu₂O(s)+ O₂(g)→ 4 CuO(s)

When 5.00 × 10²² molecules of ammonia react with 4.00 × 10²² molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH₃(g)+ 3 O₂(g)→ 2 N₂(g)+ 6 H₂O(g)

What is the mass of 8.50 × 10²² molecules of NH₃?

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s)+ 3 O₂(g)+ 4 NaOH(aq)→ 2 Na₂SO₄(aq)+ 2 H₂O(l)

A student dissolved 3.00 g of Co(NO₃)₂ in enough water to make 100.mL of stock solution.He took 4.00 mL of the solution then diluted it with water to give 275 mL of a final solution.How many grams of NO₃^- ion are there in the final solution?

Reaction of A (unshaded spheres)with B₂ (shaded spheres)is shown schematically in the following diagram.Which equation best describes the stoichiometry of the reaction?

Glucose,C₆H₁₂0₆,can be represented by the molecular model shown below.If 1.00 mol of glucose is submitted to combustion analysis,how many moles of CO₂ and how many moles of H₂O would be formed?