Chemistry Unit 4: Stoichiometry Test Review

Same number of each kind of atom appears in the reactants and in the products

A chemical equation is balanced when the

Percentage yield

A chemist interested in the efficiency of a chemical reaction would calculate the

1,12,3,4

Balance the following equation: _____Al4C3 + _____H2O - _____ CH4 + _____ Al(OH)3

1,2,1,2

Balance the following equation: _____CH4 + _____ O2 - ______ CO2 + _____ H2O

4.5 g

For the reaction represented by the equation 2 Na + 2H2O - 2NaOH + H2, how many grams of hydrogen are produced if 120 g of sodium and 80 g of water are available?

108 g

For the reaction represented by the equation 2H2 + O 2 - 2H2O, how many grams of water are produced from 6.00 mol of hydrogen?

6.23 mol

For the reaction represented by the equation CH4 + 2O2 - CO2 + 2H2O, how many moles of carbon dioxide are produced from the combustion of 100 g of methane?

188 g

For the reaction represented by the equation Cl2 + 2KBr - 2KCl + Br2, how many grams of potassium chloride can be produced from 300 g each of chlorine and potassium bromide?

93.9%

For the reaction represented by the equation SO3 + H20 - H2SO4, calculate the percentage yield if 500 g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid

The mass of the reactants equals the mass of the products

In a chemical reaction

( aq)

In an equation, the symbol for a substance in water solution is followed by

4.5 mol

In the equation 2KClO3 - 2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely?

4:3

In the reaction represented by the equation 2Al2O3 - 4Al + 3O2, what is the mole ratio of aluminum to oxygen?

1:2

In the reaction represented by the equation N2 + 3H2 - 2NH3, what is the mole ration of nitrogen to ammonia?

Synthesis reaction

In what kind of reaction do two or more substances combine to form a new compound?

Decomposition reaction

In what kind of reaction does a single compound produce two or more simpler substances?

H2

In writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is

2.1 g O3

Ozone, O3, is produced by the reaction represented by the following equation: NO2(g) + O2(g) - NO(g) + O3(g) What mass of ozone will form from the reaction of 2.0 g of NO2 in a car's exhaust and excess oxygen?

Combustion; C3H8+ O2 - 3CO2 + 4H2O

Tell what type of chemical reaction is represented by the following formula equation. Then balance the equation C3H8 + O2 - CO2 +H20

Synthesis; 2Ga + 3S - Ga2S3

Tell what type of chemical reaction is represented by the following formula equation. Then balance the equation. Ga + S - Ga2S3

Double Replacement; 2KBr + Mg(OH)2 - 2KOH + MgBr2

Tell what type of chemical reaction is represented by the following formula equation. Then balance the equation. KBr + Mg(OH)2 - KOH + MgBr2

Relative numbers of moles of reactants and products

The coefficients in a chemical equation represent the

Single - displacement reaction

The equation A + BX - AX + B is the general equation for a

Synthesis reaction

The equation A + X - AX is the general equation for a

Decomposition reaction

The equation AX - A + X is the general equation for a

Double - displacement reaction

The equation AZ + BY - AY + BX is the general equation for a

Synthesis reaction

The reaction represented by the equation 2 Mg(s) + O2(g) - 2 MgO(s) is a

Decomposition reaction

The reaction represented by the equation 2HgO(s) - 2Hg(l) + O2(g) is a(n)

Single-displacement reaction

The reaction represented by the equation Mg(s) + 2HCl(aq) - H2(g) + MgCl2(aq) is a

Double-displacement reaction

The reaction represented by the equation Pb(NO3)2(aq) + 2KI(aq) - PbI2(s) + 2KNO3(aq) is a

Coefficients

To balance a chemical equation, it may be necessary to adjust the

Available amount of exact reactant

To determine the limiting reactant in a chemical reaction, one must know the

Theoretical yield

What is the maximum possible amount of product obtained in a chemical reaction?

Actual yield

What is the measured amount of a product obtained from a chemical reaction?

A coefficient

What is the small whole number that appears in front of a formula in a chemical equation?

Reaction stoichiometry

What is the study of the mass relationships among reactants and products in a chemical reaction?

Composition stoichiometry

What is the study's of the mass relationships of elements in compounds?

A precipitate

When a solid produced by a chemical reaction separates from the solution it is called

9

When the equation Fe3O4 + Al - Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?

Reaction stops

When the limiting reactant in a chemical reaction is completely used, the

1,1,1

Which coefficients correctly balance the formula equation CaO + H2O - Ca(OH)2

1,1,2

Which coefficients correctly balance the formula equation NH4NO2(s) - N2(g) + H2O(l)?

Change in total mass of substances

Which observation does NOT indicate that a chemical reaction has occurred?

The amount of energy required to break the ionic bonds in calcium fluoride

Which of the following would NOT be studied in the branch of chemistry called stoichiometry?

Limiting reactant

Which reactant controls the amount of product formed in a chemical reaction?

Fe + 2CuNO3 - Fe(NO3)2 + 2Cu

Write a balanced equation for the following reaction: Iron plus copper (I) nitrate yields iron (II) nitrate plus copper