Questions 8.1 and 8.2: Writing and Balancing Chemical Equations Include phases of matter for ALL reactants and products.
Circle the chemical formula of the precipitate, if any, in each reaction.
Balance all chemical equations.
1. Write a chemical equation for the reaction that occurs when solid sodium oxide is added to water at room temperature to yield sodium hydroxide . (Check the Solubility Rules to determine the phase of matter of sodium hydroxide.)
Na2O (s) + H2O (l) → 2 NaOH (aq)
2. Translate the following chemical equation into a sentence.
PbCl2 (aq) + Na2CrO4 (aq) → PbCrO4 ↓ + 2NaCl (aq)
Aqueous solutions of lead (II) chloride and sodium chromate react to yield solid lead (II) chromate and aqueous sodium chloride.
3. Write the chemical equations for the following reactions.
a. When heated, solid calcium reacts with solid sulfur to produce solid calcium sulfide.
Ca (s) + S (s) → CaS (s)
b. Hydrogen gas reacts with fluorine gas to produce hydrogen fluoride gas.
H2 (g) + F2 (g) → 2 HF(g)
c. Solid aluminum metal reacts with aqueous zinc chloride to produce solid zinc metal and aluminum chloride. (Check the Solubility Rules to determine the phase of matter of aluminum chloride.)
2 Al (s) + 3 ZnCl2 (aq) → 2 Zn (s) + 2 AlCl3 (aq)
4. Translate the following chemical equations into sentences.
a. CS2 (l) + 3O2 (g) → CO2 (g) + 2SO2 (g)
Liquid carbon disulfide reacts with elemental oxygen to yield carbon dioxide gas and sulfur dioxide gas.
b. NaCl (aq) + AgNO3 (aq) → NaNO3 (aq) + AgCl (s)
Solutions of sodium chloride and silver nitrate react to yield aqueous sodium nitrate and solid silver chloride.
5. Write the chemical equation for the reaction of elemental zinc with hydrochloric acid, HCl, to produce a