Question

For each of the following

i) write a skeleton equation
ii) write a correct balanced chemical equation
iii) classify reaction by type

1) calcium metal and water react, giving hydrogen gas and calcium hydroxide

2) aluminum metal quickly reacts with the oxygen in the air to produce aluminum oxide

3) hydrogen sulphate (sulphutic acid) and sodium hydroxide react, producing sodium sulphate and water.

4) sodium chloride and oxygen are produced by heating sodium chlorate.

5) silver nitrate and potassium phosphate react together producing silver phosphate and potassium nitrate.

6) aluminum oxide and copper metal are the products of a reaction between copper (II) oxide and aluminum metal.

7)magnesium and phosphorus (P4) react together, producing magnesium phosphide.

8) lead (II) nitrate and potassium iodide react producing lead (II) iodide a bright yellow precipitate and potassium nitrate which stays in solution. ​​

Answer 1

1) Calcium metal and water react, giving hydrogen gas and calcium hydroxide

• Ca(s) + H2O Ca(OH)2 (aq) + H2(g)

• Ca(s) + 2H2O Ca(OH)2 (aq) + H2(g)

• Exothermic combination reaction

2) aluminum metal quickly reacts with the oxygen in the air to produce aluminum oxide

• Al + 02 = Al2O3

• 4 Al + 302 = 2Al2O3

• Combination reaction

3) Hydrogen sulphate (sulphutic acid) and sodium hydroxide react, producing sodium sulphate and water.

• NaOH + H2SO4 = Na2SO4 + 2H2O

• 2NaOH + H2SO4 = Na2SO4 + 2H2O

• Double Displacement reaction

4) sodium chloride and oxygen are produced by heating sodium chlorate.

• NaclO3 = NaCl + O

• 2NaclO3 = 2NaCl + 3 O

• Decomposition reaction

6) aluminum oxide and copper metal are the products of a reaction between copper (II) oxide and aluminum metal.

• Al + CuO = Al2O3 + Cu

• 2 Al + 3CuO = Al2O3 + 3 Cu

• Oxidation and Reduction

8) lead (II) nitrate and potassium iodide react producing lead (II) iodide a bright yellow precipitate and potassium nitrate which stays in solution.

• Pb(No3)2 +KI = PbI2 + KNO3

• Pb(No3)2 +2KI = PbI2 + 2KNO3

• Double displacement reaction

Step-by-step explanation:

Answer 2

1. Skeleton: Ca + H₂O ⇒ H₂ + Ca(OH)₂

Balanced: Ca + 2H₂O ⇒ H₂ + Ca(OH)₂

Type: Single displacement / single replacement

2. Skeleton: Al + O₂ ⇒ Al₂O₃

Balanced: 4Al + 3O₂ ⇒ 2Al₂O₃

Type: Synthesis

3. Skeleton: H₂SO₄ + NaOH ⇒ Na₂SO₄ + H₂O

Balanced: H₂SO₄ + 2NaOH ⇒ Na₂SO₄ + 2H₂O

Type: Double displacement / double replacement

4. Skeleton: NaClO₃ ⇒ NaCl + O₂

Balanced: 2NaClO₃ ⇒ 2NaCl + 3O₂

Type: Decomposition

5. Skeleton: AgNO₃ + K₃PO₄ ⇒ Ag₃PO₄ + KNO₃

Balanced: 3AgNO₃ + K₃PO₄ ⇒ Ag₃PO₄ + 3KNO₃

Type: Double displacement / double replacement

6. Skeleton: Cu(OH)₂ + Al ⇒ Al(OH)₃ + Cu

Balanced: 3Cu(OH)₂ + 2Al ⇒ 2Al(OH)₃ + 3Cu

Type: Single replacement / single displacement

7. Skeleton: Mg + P₄ ⇒ Mg₃P₂

Balanced: 6Mg + P₄ ⇒ 2Mg₃P₂

Type: Synthesis

8. Skeleton: KNO₃ + PbI₂ ⇒ KI + Pb(NO₃)₂

Balanced: 2KNO₃ + PbI₂ ⇒ 2KI + Pb(NO₃)₂