Chapter U4, Problem SI4RE

(a)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of nitrogen gas and hydrogen gas needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{N}}_{\text{2}}{\text{(g) + 2H}}_{\text{2}}\text{(g) }\to {\text{ N}}_{\text{2}}{\text{H}}_{\text{4}}\text{(g)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{N}}_{\text{2}}{\text{(g) + H}}_{\text{2}}\text{(g) }\to {\text{ N}}_{\text{2}}{\text{H}}_{\text{4}}\text{(g)}$

To balance the above reaction, give coefficient 2 to H₂ thus, the balanced chemical reaction will be as follows:

  ${\text{N}}_{\text{2}}{\text{(g) + 2H}}_{\text{2}}\text{(g) }\to {\text{ N}}_{\text{2}}{\text{H}}_{\text{4}}\text{(g)}$

(b)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of potassium nitrate and potassium metal needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{2KNO}}_{\text{3}}\text{(s) + 10K(s) }\to {\text{ 6K}}_{\text{2}}{\text{O(s) + N}}_{\text{2}}\text{(g)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{KNO}}_{\text{3}}\text{(s) + K(s) }\to {\text{ K}}_{\text{2}}{\text{O(s) + N}}_{\text{2}}\text{(g)}$

To balance the above reaction, give coefficient 2 to KNO₃, 10 to K and 6 to K₂O, balanced chemical reaction will be as follows:

  ${\text{2KNO}}_{\text{3}}\text{(s) + 10K(s) }\to {\text{ 6K}}_{\text{2}}{\text{O(s) + N}}_{\text{2}}\text{(g)}$

(c)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of aqueous sulfuric acid and aqueous sodium cyanide needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq) + 2NaCN(aq) }\to {\text{ 2HCN(g) + Na}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq) + NaCN(aq) }\to {\text{ HCN(g) + Na}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq)}$

To balance the above reaction, give coefficient 2 to NaCN and 2 to HCN, balanced chemical reaction will be as follows:

  ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq) + 2NaCN(aq) }\to {\text{ 2HCN(g) + Na}}_{\text{2}}{\text{SO}}_{\text{4}}\text{(aq)}$

(d)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of phosphoric acid and calcium hydroxide needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{2H}}_3{\text{PO}}_{\text{4}}{\text{(aq) + 3Ca(OH)}}_{\text{2}}\text{(aq) }\to {\text{ Ca}}_{\text{3}}{{\text{(PO}}_{\text{4}}\text{)}}_{\text{2}}{\text{(aq) + 6H}}_{\text{2}}\text{O(l)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{H}}_3{\text{PO}}_{\text{4}}{\text{(aq) + Ca(OH)}}_{\text{2}}\text{(aq) }\to {\text{ Ca}}_{\text{3}}{{\text{(PO}}_{\text{4}}\text{)}}_{\text{2}}{\text{(aq) + H}}_{\text{2}}\text{O(l)}$

To balance the above reaction, give coefficient 2 to H₃PO₄, 3 to Ca(OH)₂ and 6 to H₂O, thus, the balanced chemical reaction will be as follows:

  ${\text{2H}}_3{\text{PO}}_{\text{4}}{\text{(aq) + 3Ca(OH)}}_{\text{2}}\text{(aq) }\to {\text{ Ca}}_{\text{3}}{{\text{(PO}}_{\text{4}}\text{)}}_{\text{2}}{\text{(aq) + 6H}}_{\text{2}}\text{O(l)}$

(e)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of propane and oxygen gas needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{(g) + 5O}}_{\text{2}}\text{(g) }\to {\text{ 3CO}}_{\text{2}}{\text{(g) + 4H}}_{\text{2}}\text{O(l)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{(g) + O}}_{\text{2}}\text{(g) }\to {\text{ CO}}_{\text{2}}{\text{(g) + H}}_{\text{2}}\text{O(l)}$

To balance the above reaction, give coefficient 5 to O₂, 3to CO₂ and 4 to H₂O thus, the balanced chemical equation will be:

  ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}{\text{(g) + 5O}}_{\text{2}}\text{(g) }\to {\text{ 3CO}}_{\text{2}}{\text{(g) + 4H}}_{\text{2}}\text{O(l)}$

(f)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of hydrogen sulfide and oxygen gas needs to be determined

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{2H}}_2{\text{S(g) + 3O}}_{\text{2}}\text{(g) }\to {\text{ 2SO}}_{\text{2}}{\text{(g) + 2H}}_{\text{2}}\text{O(l)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{H}}_2{\text{S(g) + O}}_{\text{2}}\text{(g) }\to {\text{ SO}}_{\text{2}}{\text{(g) + H}}_{\text{2}}\text{O(l)}$

To balance the above reaction, give coefficient 2 to H₂S, 3to O₂, 2 to SO₂ and 2 to H₂O thus, the balanced chemical equation will be:

  ${\text{2H}}_2{\text{S(g) + 3O}}_{\text{2}}\text{(g) }\to {\text{ 2SO}}_{\text{2}}{\text{(g) + 2H}}_{\text{2}}\text{O(l)}$

(g)

Interpretation Introduction

Interpretation: The balanced chemical equation for the given chemical reaction of hydrogen and oxygen gas needs to be determined.

Concept Introduction:

The chemical reaction must be balanced such that it agrees with the law of mass conservation. A balanced chemical equation arises when the number of atoms or ions of the reactant side equals the number of atoms or ions of the product side.

Answer to Problem SI4RE

The balanced chemical equation is:

  ${\text{2H}}_2{\text{(g) + O}}_{\text{2}}\text{(g) }\to {\text{ 2H}}_{\text{2}}\text{O(l)}$

Explanation of Solution

The unbalanced chemical reaction is as follows:

  ${\text{H}}_2{\text{(g) + O}}_{\text{2}}\text{(g) }\to {\text{ H}}_{\text{2}}\text{O(l)}$

To balance the above reaction, give coefficient 2 to H₂and 2 to H₂O thus, the balanced chemical equation will be:

  ${\text{2H}}_2{\text{(g) + O}}_{\text{2}}\text{(g) }\to {\text{ 2H}}_{\text{2}}\text{O(l)}$