chemistry semester final ch.8

A reaction of a hydrocarbon, in which carbon dioxide and water are produced, is classified as a a. decomposition reaction. c. double-displacement reaction. b. combustion reaction. d. synthesis reaction

combustion reaction

Which equation is NOT balanced? a. 2H2 + O2 → 2H2O c. H2 + H2 + O2 → H2O + H2O b. 4H2 + 2O2 → 4H2O d. 2H2 + O2 → H2O

d

In what kind of reaction does a single compound produce two or more simpler substances? a. decomposition reaction c. displacement reaction b. synthesis reaction d. ionic reaction

decomposition reaction

The equation AX ---> A + X is the general equation for a a) synthesis reaction b) decomposition reaction c) combustion reaction d) single-replacement reaction

decomposition reaction

The reaction 2HgO(s)---> 2Hg(l) + O2 (g) is a(n) a) single-replacement reaction. b) synthesis reaction. c) ionic reaction. d) decomposition reaction.

decomposition reaction

The reaction 2KClO3(s) → 2KCl(s) + 3O2(g) is a(n) a. synthesis reaction. c. combustion reaction. b. decomposition reaction. d. ionic reaction.

decomposition reaction

. The equation A + BX → AX + B is the general equation for a a. double-displacement reaction. c. displacement reaction. b. decomposition reaction. d. combustion reaction

displacement reaction

In what kind of reaction does one element replace a similar element in a compound? a. displacement reaction c. decomposition reaction b. combustion d. ionic reaction

displacement reaction

The reaction Cl2(g) + 2KBr(aq) → 2KCl(aq) + Br2(l) is a(n) a. synthesis reaction. c. displacement reaction. b. ionic reaction. d. combustion reacti

displacement reaction

The equation AX + BY ---> AY + BX is the general equation for a(n) a) synthesis reaction b) decomposition reaction c) single-replacement reaction d) double-replacement reaction

double displacement reaction

If chlorine gas is produced by halogen replacement, the other halogen in the reaction must be a. bromine. c. astatine. b. iodine. d. fluorine

fluorine

After the correct formula for a reactant in an equation has been written, the a. subscripts are adjusted to balance the equation. b. formula should not be changed. c. same formula must appear as the product. d. symbols in the formula must not appear on the product side of the equation.

formula should not be changed

If metal X is lower than metal Y in the activity series, then metal X a. replaces ions of metal Y in a solution. b. is more active than metal Y. c. is less active than metal Y. d. forms positive ions more readily than does metal Y.

is less active than metal Y

In the unbalanced formula equation CO + O2 → CO2 + energy, energy a. is absorbed. c. is released. b. can be considered a reactant. d. Both (a) and (b)

is released

Knowledge about what products are produced in a chemical reaction is obtained by a. inspecting the chemical equation. c. laboratory analysis. b. balancing the chemical equation. d. writing a word equation

laboratory analysis

in one type of synthesis reaction, an element combines with oxygen to yield a(n) a. acid. c. oxide. b. hydroxide. d. metal.

oxide

When a metal chlorate is heated, it decomposes to yield a metal chloride and a. a metal oxide. c. hydrogen. b. a metal hydroxide. d. oxygen

oxygen

A precipitate forms in a double-displacement reaction when a. hydrogen gas reacts with a metal. b. positive ions combine with negative ions. c. water boils out of the solution. d. a gas escapes.

positive ions combine with negative ions

A solid produced by a chemical reaction in solution that separates from the solution is called a) a precipitate b) a reactant c) a molecule d) the mass of the product

precipitate

A chemical equation is balanced when the a. coefficients of the reactants equal the coefficients of the products. b. same number of each kind of atom appears in the reactants and in the products. c. products and reactants are the same chemicals.

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

The state of matter for a reactant or a product in a chemical equation is indicated by a a. coefficient before the formula. c. symbol after the formula. b. subscript after the formula. d. superscript after the formula

symbol after the formula

In what kind of reaction do two or more substances combine to form a new compound? a. decomposition reaction c. double-displacement reaction b. ionic reaction d. synthesis reaction

synthesis reaction

The equation A + X → AX is the general equation for a(n) a. combustion reaction. c. synthesis reaction. b. ionic reaction. d. double-displacement reaction.

synthesis reaction

The reaction 2Mg(s) + O2 (g) ----> 2MgO(s) is a a) synthesis reaction b) decomposition reaction c) single-replacement reaction d) double-replacement reaction

synthesis reaction

A chemical reaction has NOT occurred if the products have a. the same mass as the reactants. b. more energy than the reactants. c. less energy than the reactants. d. the same chemical properties as the reactants

the same chemical properties as the reactants

When a binary compound decomposes, what is produced? a) an oxide b) an acid c) a tertiary compound d) two elements

two elements

Many metal hydroxides decompose when heated to yield metal oxides and a. metal hydrides. c. carbon dioxide. b. water. d. an acid.

water

What can be predicted by using an activity series? a. whether a certain chemical reaction will occur b. the amount of energy released by a chemical reaction c. the electronegativity values of elements d. the melting points of elements

whether a certain chemical reaction will occur

Which coefficients correctly balance the formula equation CaCO3(s) → CaO(s) + CO2(g)? a. 1, 1, 1 c. 2, 6, 3 b. 1, 3, 1 d. 3, 1, 2

1 1 1

Which coefficients correctly balance the formula equation CaO + H2O → Ca(OH)2? a. 2, 1, 2 c. 1, 2, 1 b. 1, 2, 3 d.. 1, 1, 1

1 1 1

Which coefficients correctly balance the formula equation NH4NO2 → N2 + H2O? a. 1, 2, 2 c. 2, 1, 1 b. 1, 1, 2 d. 2, 2, 2

1 1 2

Which coefficients correctly balance the formula equation Zn(OH)2 + CH3COOH → Zn(CH3COO)2 + H2O? a. 1, 2, 1, 1 c. 1, 2, 1, 2 b. 2, 1, 2, 1 d. 2, 1, 1, 2

1 2 1 2

When the equation Fe3O4 + Al --> Al2O3 + Fe is correctly balanced, what is the coefficient of Fe? a) 3 b) 4 c) 6 d) 9

9

The reaction, C2H5OH + 3O2 ⎯⎯heat⎯→ 2CO2 + 3H2O, will occur most rapidly if a. C2H5OH is a liquid and O2 is a liquid. c. CO2 is a gas and H2O is a liquid. b. C2H5OH and O2 are in close contact. d. CO2 is a gas and H2O is a gas.

C2H5OH and O2 are in close contact.

The word equation solid carbon + oxygen gas → carbon dioxide gas + energy, represents a chemical reaction because a. the reaction releases energy. b. CO2 has chemical properties that differ from those of C and O. c. the reaction absorbs energy. d. CO2 is a gas and carbon is a crystal.

CO2 has chemical properties that differ from those of C and O.

In writing an equation that produces hydrogen gas, the correct representation of hydrogen gas is a) H b) 2H c) H2 d) OH

H2

. In the word equation, sodium oxide + water sodium hydroxide, the formula for sodium hydroxide is represented by a. Na2OH. c. NaO2. b. NaOH. d. Na2O.

NaOH

How would oxygen be represented in the formula equation for the reaction of methane and oxygen to yield carbon dioxide and water? a. oxygen c. O2 b. O d. O3

O2

The formulas for the products of the reaction between sodium hydroxide and sulfuric acid are a. Na2SO4 and H2O. c. SI4 and Na2O. b. NaSO4 and H2O. d. S + O2 and Na.

a

A chemical formula written over the arrow in a chemical equation signifies a. a by-product. c. a catalyst for the reaction. b. the formation of a gas. d. an impurity.

a catalyst for the reaction

What is the number that appears in front of a formula in a chemical equation called? a. a subscript c. a proportion b. a superscript d. a coefficient

a coefficient

An insoluble solid produced by a chemical reaction in solution is called a. a precipitate. c. a molecule. b. a reactant. d. the mass of the product.

a precipitate

What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions? a. reactivity list c. activity series b. reaction sequence d. periodic list

activity series

After the first steps in writing an equation, the equation is balanced by a. adjusting subscripts to the formula(s). b. adjusting coefficients to the smallest whole-number ratio. c. changing the products formed. d. making the number of reactants equal to the number of products

adjusting coefficients to the smallest whole-number ratio

According to the law of conservation of mass, the total mass of the reacting substances is A. always more than the total mass of the products. B. always less than the total mass of the products. C. sometimes more and sometimes less than the total mass of the products. D. always equal to the total mass of the products.

always equal to the total mass of the products

In an equation, the symbol for a substance in a water solution is followed by a) (l). b) (g). c) (aq). d) (s).

aq

The products of the reaction, C2H5OH + 3O2 → 2CO2 + 3H2O have the same _____ as the reactants. a. atoms. c. molecules. b. coefficients. d. subscripts

atoms

The word equation for the formula equation shown is C2H5OH + O2 → CO2 + H2O + energy a. carbon dioxide + water → ethanol + oxygen + energy. b. ethanol + oxygen → carbon dioxide + water + energy. c. ethanol + oxygen + energy → carbon dioxide + water. d. ethanol + oxygen + energy → carbon dioxide + water + energy

b

What is the balanced equation when aluminum reacts with copper(II) sulfate? a. Al + Cu2S → Al2S + Cu c. Al + CuSO4 → AlSO4 + Cu b. 2Al + 3CuSO4 → Al2(SO4)3 + 3Cu d. 2Al + Cu2SO4 → Al2SO4 + 2Cu

b

Which of the following is the correct chemical equation for the formation of carbon dioxide from carbon and oxygen? a) 2C + 2O2 --> CO2 b) C + O2 ---> CO2 c) CO2 ---> C + O2 d) 2C + O ---> CO2

b

An element in the activity series can replace any element a. in the periodic table. c. above it on the list. b. below it on the list. d. in its group.

below it on the list

The complete balanced equation for the reaction between zinc II hydroxide and acetic acid is a) ZnOH + CH3COOH ---> ZnCH3COO + H2O b) Zn(OH)2 + CH3COOH ---> Zn + 2CO2 + 3H2O c) Zn(OH)2 + 2CH3COOH ---> Zn(CH3COO)2 + 2H2O d) Zn(OH)2 + 2CH3COOH ---> Zn(CH3COO)2 + O2 + H2

c

Which observation does NOT indicate that a chemical reaction has occurred? a. formation of a precipitate c. evolution of energy b. production of a gas d. change in total mass of substances

change in total mass of substances