Chapter U4, Problem SII6RE

(a)

Interpretation Introduction

Interpretation:

The balanced chemical equation for the reaction of solid titanium tetrachloride and magnesium 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 reactant side are equals to the number of atom or ions of product side.

Answer to Problem SII6RE

  ${\text{TiCl}}_{\text{4}}\text{(s) + 2Mg(s) }\to {\text{ Ti(s) + 2MgCl}}_{\text{2}}\text{(s)}$

Explanation of Solution

When the solid titanium tetrachloride react with magnesium metal it will give titanium solid and solid magnesium chlorides.

Unbalance reaction

  ${\text{TiCl}}_{\text{4}}\text{(s) + Mg(s) }\to {\text{ Ti(s) + MgCl}}_{\text{2}}\text{(s)}$

The reaction can be balanced by giving coefficient 2 to Mg and 2 to MgCl₂ as follows:

  ${\text{TiCl}}_{\text{4}}\text{(s) + 2Mg(s) }\to {\text{ Ti(s) + 2MgCl}}_{\text{2}}\text{(s)}$

(b)

Interpretation Introduction

Interpretation:

The balanced chemical equation for magnesium metal and water 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 reactant side are equals to the number of atom or ions of product side.

Answer to Problem SII6RE

  ${\text{Mg(s) + H}}_{\text{2}}\text{O(l) }\to {\text{ MgO(s) + H}}_{\text{2}}\text{(g)}$

Explanation of Solution

Solid magnesium reacts with water molecule which gives magnesium oxide (MgO) and release the hydrogen gas.

Unbalance reaction:

  ${\text{Mg(s) + H}}_{\text{2}}\text{O(l) }\to {\text{ MgO(s) + H}}_{\text{2}}\text{(g)}$

The above reaction is already balanced.

(c)

Interpretation Introduction

Interpretation:

The balanced chemical equation for iron metal and solid copper sulphate 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 reactant side are equals to the number of atom or ions of product side.

Answer to Problem SII6RE

  ${\text{Fe(s) + CuSO}}_{\text{4}}\text{(s) }\to {\text{ FeSO}}_{\text{4}}\text{(s) + Cu(g)}$

Explanation of Solution

When iron metal react with solid copper sulphate, then iron metal replace the copper from copper sulphate and make solid iron sulphate and copper metal. This is also called redox reaction because oxidation and reduction takes place in this reaction.

Unbalance reaction;

  ${\text{Fe(s) + CuSO}}_{\text{4}}\text{(s) }\to {\text{ FeSO}}_{\text{4}}\text{(s) + Cu(g)}$

The above reaction is already balanced.

(d)

Interpretation Introduction

Interpretation:

The balanced chemical equation for the reaction of lithium metal and water 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 reactant side are equals to the number of atom or ions of product side.

Answer to Problem SII6RE

  ${\text{2Li(s) + 2H}}_{\text{2}}\text{O(l) }\to {\text{ 2LiOH(aq) + H}}_{\text{2}}\text{(g)}$

Explanation of Solution

Lithium metal reacts with water, which are the formation of lithium hydroxide in aqueous form and release the hydrogen gas.

Unbalance reaction;

  ${\text{Li(s) + H}}_{\text{2}}\text{O(l) }\to {\text{ LiOH(aq) + H}}_{\text{2}}\text{(g)}$

The above reaction can be balanced by giving coefficient 2 to Li, 2 to H₂O and 2 to LiOH.

  ${\text{2Li(s) + 2H}}_{\text{2}}\text{O(l) }\to {\text{ 2LiOH(aq) + H}}_{\text{2}}\text{(g)}$