Question

Identify the type of chemical reactions.
(a) H₂ + Cl₂ → 2HCl
(b) CaO + H₂O → Ca (OH)₂
(c) CaCO₃ → CaO + CO₂
(d) FeSO₄ + Mg → MgSO₄ + Fe
(e) 2KI + Pb (NO₃)2 → 2KNO₃ + Pbl₂

Answer 1

Reaction:
(a) H₂ + Cl₂ → 2HCl
Explanation:
Two elements H₂ and Cl₂ combine to form a single compound, HCl. Hence, it is a combination reaction. As two elements combine to form a compound, it is an element – element combination.
(b) CaO + H₂O → Ca(OH)₂
Explanation:
Two compound CaO and HaO combine to form a single compound, Ca (OH)₂. Hence, it is a combination reaction. As two compounds combine to form a new compound, it is a compound – compound combination.
(c) CaCO₂ → CaO + CO₂
Explanation:
The compound CaCO₃ splits (decompose) into two compounds, CaO and
COO. Hence, it is a compound-com¬pound combination.
(d) FeSO₄ + Mg → MgSO₄ + Fe
Explanation:
Here magnesium (Mg) is displacing, iron (Fe) from its salt solution (FeSO₄). Hence, it is a displacement reaction.
(e) 2KI + Pb (NO₃)₂ → 2KNO₃ + Pbl₂
Explanation:
The reactants potassium iodide and lead nitrate react to form potassium nitrate and lead iodide. From this it is clear that, radicals are intercharged by the decomposition of reactants. Hence, it is a double decomposition reaction.