Chemical Reaction Test

Which is NOT an indications that a chemical reaction has occurred?

• Temperature Change

• Taste change

• Color Change

• Bubbles

Which of the following are decomposition reactions?

• CH4 (g) + O2 (g) → CO2 (g) + H2O (1)

• CaO (s) + CO2 (g) → CaCO3 (s)

• Mg (s) + O2 (g) → MgO (s)

• PbCO3 (s) → PbO (s) + CO2 (g)

When propane is reacted in the presence of oxygen gas, the products of this combustion reaction are:

• CO2 + H2

• C + H2

• CO2 + H2O

• CH2 + H2O

In a decomposition reaction:

• the reactants are generally two ionic compounds in aqueous solution

• energy in the form of heat or light is often needed

• one of the reactants is often water

• the reactants are usually a metal and a nonmetal

Combination reactions always:

• involve an element and an ionic compound

• form only one product

• require oxygen gas

• use only one reactant

Of the balanced chemical equations below, which one most correctly represents a combustion reaction?

• 2 Mg + 02 → 2 MgO

• 2 CH4 + 4 O2 → 2 CO2 + 4H2O

• CaO + H2O Ca(OH)2

• 2 N2 + 3 H2 → 2 NH3

Which chemical equation correctly represents the decomposition reaction that takes place when ammonia breaks down to form hydrogen gas and nitrogen gas?

• NH3 + H2 → N2

• NH3 → N+H

• NH3 → N2 + H2

• N2 + H2 → NH3

The chemical equation, KCIO3 → KCI + O2, is an example of which type of reaction?

• decomposition

• double-replacement

• combustion

• single-replacement

In the following chemical reaction, what product is represented by X? AICI3+ NaOH → X + NaCl

• Al3OH

• AIOH

• It cannot be determined.

• Al(OH)3

The chemical equation, Cr + Fe(NO3)2 → Fe + Cr(NO3)3, is an example of which type of reaction?

• combustion

• single-replacement

• double-replacement

• decomposition