Chemistry Daily 10’s

Week 12

1

1. In a chemical reactiona. the mass of the reactants equals the mass of

the products.b. the mass of the products is greater than the

mass of reactants.c. the number of atoms in the reactants and

products must change.d. energy as heat must be added to the reactants.

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

a. H.b. 2H.c. H2.

d. OH.

2

1. Which of the following is a formula equation for the formation of carbon dioxide from carbon and oxygen?

a. Carbon plus oxygen yields carbon dioxide.b. C + O2 CO2

c. CO2 C + O2

d. 2C + O CO2

2. A chemical formula written over the arrow in a chemical equation signifies

a. a by-product.b. the formation of a gas.c. a catalyst for the reaction.d. an impurity.

3

1. Which coefficients correctly balance the formula equation

NH4NO2(s)N2(g) + H2O(l)?

a. 1, 2, 2b. 1, 1, 2c. 2, 1, 1d. 2, 2, 2

2. In what kind of reaction does one element replace a similar element in a compound?

a. displacement reactionb. combustionc. decomposition reactiond. ionic reaction

4

1. In what kind of reaction do the ions of two compounds exchange places in aqueous solution to form two new compounds?

a. synthesis reactionb. double-displacement reactionc. decomposition reactiond. combustion reaction

2. The reaction represented by the equation 2KClO3(s) 2KCl(s) + 3O2(g) is a(n)

a. synthesis reaction.b. decomposition reaction.c. combustion reaction.d. ionic reaction.

5

1. If chlorine gas is produced by halogen replacement, the other halogen in the reaction must be

a. bromine.b. iodine.c. astatine.d. fluorine.

2. Which reaction does not occur?a. 2HF(aq) + Cl2(g) F2(g) + 2HCl(aq)

b. 2Na(s) + ZnF2(aq) 2NaF(aq) + Zn(s)

c. Fe(s) + CuCl2(aq) FeCl2(aq) + Cu(s)

d. 2HCl(aq) + Mg(s) MgCl2(aq) + H2(g)

Answers & Standards

• 1.1 – a – sc2b• 1.2 – c – sc2a• 2.1 - b – sc2a• 2.2 - c – sc2a• 3.1 - b – sc2a• 3.2 - a – sc2a• 4.1 - b – sc2a• 4.2 - b – sc2a• 5.1 - d – sc2a• 5.2 - a – sc2a