# Last night’s homework:

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Last night’s homework:
Problems 4-6 on page 282 Questions 7-11 on page 283

Write chemical equations for each of the following reactions.

In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride.

In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride.

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl
In water, iron(III) chloride reacts with sodium hydroxide, producing solid iron(III) hydroxide and sodium chloride. FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + NaCl

FeCl3 + NaOH → Fe(OH)3 + 3NaCl

FeCl3 + NaOH → Fe(OH)3 + 3NaCl

FeCl3 + NaOH → Fe(OH)3 + 3NaCl

FeCl3 + 3NaOH → Fe(OH)3 + 3NaCl

FeCl3 + 3NaOH → Fe(OH)3 + 3NaCl

FeCl3 + 3NaOH → Fe(OH)3 + 3NaCl

5. Liquid carbon disulfide reacts with oxygen gas, producing carbon dioxide gas and sulfur dioxide gas.

5. Liquid carbon disulfide reacts with oxygen gas, producing carbon dioxide gas and sulfur dioxide gas. CS2 + O2 → CO2 + SO2

CS2 + O2 → CO2 + SO2

CS2 + O2 → CO2 + SO2 C O S C O S

CS2 + O2 → CO2 + SO2 C 1 O 2 S 2 C 1 O 4 S 1

CS2 + O2 → CO2 + 2SO2 C 1 O 2 S 2 C 1 O 4 S 1

CS2 + O2 → CO2 + 2SO2 C 1 O 2 S 2 C 1 O 6 S 2

CS2 + 3O2 → CO2 + 2SO2 C 1 O 2 S 2 C 1 O 6 S 2

CS2 + 3O2 → CO2 + 2SO2 C 1 O 6 S 2 C 1 O 6 S 2

CS2 + 3O2 → CO2 + 2SO2 C 1 O 6 S 2 C 1 O 6 S 2

6. Solid zinc and aqueous hydrogen sulfate react to produce hydrogen gas and aqueous zinc sulfate.

6. Solid zinc and aqueous hydrogen sulfate react to produce hydrogen gas and aqueous zinc sulfate.
Zn + H2SO4 → H2 + ZnSO4

Zn + H2SO4 → H2 + ZnSO4 Zn H S O Zn H S O

Zn + H2SO4 → H2 + ZnSO4 Zn 1 H 2 S 1 O 4 Zn 1 H 2 S 1 O 4

List three types of evidence that a chemical reaction has occurred.

Changes in: Temperature Color Appearance of: Odor Gas bubbles
List three types of evidence that a chemical reaction has occurred. Changes in: Temperature Color Appearance of: Odor Gas bubbles Solid precipitate

8. Compare and contrast a skeleton equation and a chemical equation.

Both show formulas of reactants and products.
8. Compare and contrast a skeleton equation and a chemical equation. Both show formulas of reactants and products. Chemical equation also shows relative amounts.

9. Why is it important that a chemical equation be balanced?

Mass is neither created nor destroyed.
9. Why is it important that a chemical equation be balanced? Mass is neither created nor destroyed.

10. When balancing a chemical equation, can you adjust the number that is subscripted to a substance formula?

10. When balancing a chemical equation, can you adjust the number that is subscripted to a substance formula? No

10. When balancing a chemical equation, can you adjust the number that is subscripted to a substance formula? No H2O → H2 + O2

10. When balancing a chemical equation, can you adjust the number that is subscripted to a substance formula? No H2O → H2 + O2 H2O2 → H2 + O2

11. Why is it important that to reduce the coefficients in a balanced equation to the lowest possible whole-number ratio?

. Clearly shows the relative amounts.
11. Why is it important that to reduce the coefficients in a balanced equation to the lowest possible whole-number ratio? Clearly shows the relative amounts. .