Question

Given below are word equations. Convert them into chemical equations using symbols and valences. Balance the equations. Use appropriate signs for gases and precipitates in the reaction.
i) \[{\text{Zinc Sulphide + Oxygen gas }} \to {\text{ Zinc oxide solid + Sulphur dioxide gas}}\]
ii) \[
  {\text{Silver nitrate solution + Sodium chloride solution }} \to {\text{ Silver chloride precipitate}} \\
  {\text{+ Sodium nitrate solution}} \\
 \]
iii) \[
  {\text{Sulphur solid + Concentrated nitric acid }} \to {\text{ Sulphuric acid + Nitrogen dioxide gas}} \\
  {\text{ + Water}} \\
 \]
 iv) \[
  {\text{Barium chloride Solution + Potassium sulphate Solution }} \to {\text{Barium sulphate Precipitate}} \\
  {\text{ + Potassium chloride solution}} \\
 \]
v) \[{\text{Silver nitrate on heating }} \to {\text{ silver metal + nitrogen dioxide gas + Oxygen gas}}\]
vi) \[{\text{Aluminium hydroxide + Nitric acid }} \to {\text{ Aluminium nitrate + Water}}\]

Answer 1

Hint: While balancing the chemical equation, the number of atoms of a particular atom on the left hand side of the equation should be equal to the number of atoms of that element on the right hand side of the equation. Also the sum of all the charges on the reactant side should be equal to the sum of all charges on the product side.

Complete Step by step answer:i) Solid zinc sulphide reacts with oxygen gas to form solid zinc oxide and Sulphur dioxide gas
Write balanced chemical equation for the process:
 \[{\text{ZnS}}\left( s \right){\text{ + }}{{\text{O}}_2}\left( g \right){\text{ }} \to {\text{ ZnO}}\left( s \right){\text{ + S}}{{\text{O}}_2}\left( g \right) \uparrow \]

ii) Silver nitrate solution reacts with sodium chloride solution to form silver chloride precipitate and sodium nitrate solution. Write balanced chemical equation for the process:
 \[{\text{AgN}}{{\text{O}}_3}\left( {aq} \right){\text{ + NaCl}}\left( {aq} \right){\text{ }} \to {\text{ AgCl}}\left( s \right) \downarrow {\text{ + NaN}}{{\text{O}}_3}\left( {aq} \right)\]

iii) Sulphur solid reacts with concentrated nitric acid to form sulphuric acid and nitrogen dioxide gas and water. Write balanced chemical equation for the process:
 \[{\text{S}}\left( s \right){\text{ + 4HN}}{{\text{O}}_3}\left( {aq} \right) \to {\text{ S}}{{\text{O}}_2}\left( g \right) \uparrow {\text{ + 4N}}{{\text{O}}_2}\left( g \right) \uparrow {\text{ + 2}}{{\text{H}}_2}{\text{O}}\left( l \right)\]

iv) Barium chloride solution reacts with potassium sulphate solution to form barium sulphate precipitate and potassium chloride solution. Write balanced chemical equation for the process:
 \[{\text{BaC}}{{\text{l}}_2}\left( {aq} \right){\text{ + }}{{\text{K}}_2}{\text{S}}{{\text{O}}_4}\left( {aq} \right) \to {\text{ BaS}}{{\text{O}}_4}\left( s \right) \downarrow {\text{ + KCl}}\left( {aq} \right)\]

v) Silver nitrate on heating gives silver metal, nitrogen dioxide gas and oxygen gas. Write balanced chemical equation for the process:
 \[{\text{2AgN}}{{\text{O}}_3}\left( s \right){\text{ }}\xrightarrow{\Delta }{\text{ 2 Ag}}\left( s \right) + {\text{ 2N}}{{\text{O}}_2}\left( g \right) \uparrow {\text{ + }}{{\text{O}}_2}\left( g \right) \uparrow \]

vi) Aluminium hydroxide reacts with nitric acid to form aluminium nitrate and Water. Write balanced chemical equation for the process:
 \[{\text{Al}}{\left( {{\text{OH}}} \right)_3}\left( s \right) + {\text{HN}}{{\text{O}}_3}\left( {aq} \right){\text{ }} \to {\text{Al}}{\left( {{\text{N}}{{\text{O}}_3}} \right)_3}\left( s \right) + {\text{ }}{{\text{H}}_2}{\text{O}}\left( l \right)\]


Note: The chemical symbol of zinc sulphide is \[{\text{ZnS}}\] . Zinc cation has +2 charge and sulphide anion has -2 charge. The zinc sulphide molecule will be neutral when one zinc cation combines with one zinc anion.
Aluminium hydroxide contains \[{\text{A}}{{\text{l}}^{3 + }},{\text{O}}{{\text{H}}^ - }\] ions. The aluminium hydroxide molecule will be neutral when one \[{\text{A}}{{\text{l}}^{3 + }}\] cation combines with three \[{\text{O}}{{\text{H}}^ - }\] ions.