Balance the following chemical equations and identify the type of chemical reaction.

(a) Mg(s) + Cl2(g) MgCl2(s)


(b) HgO(s) ⎯⎯⎯⎯ (Heat) Hg(l) + O2(g)


(c) Na(s) + S(s) ⎯⎯⎯⎯ (Fuse) Na2S(s)


(d) TiCl4 (l) + Mg(s) Ti(s) + MgCl2 (s)


(e) CaO(s) + SiO2(s) CaSiO3(s)


(f) H2O2 (l) ⎯⎯⎯⎯ UV H2O(l) + O2 (g)



(a) Mg(s) + Cl2(g)
MgCl2(s)
This type of reaction is called a combination reaction or a synthesis reaction.



(b) 2HgO(s)
⎯⎯⎯⎯ (Heat) 2 Hg(l) + O2(g)
This is an example of thermal decomposition reaction.



(c) 2Na(s) + S(s)
⎯⎯⎯⎯ (Fuse) Na2S(s)
This is an example of a Combination reaction.



(d) TiCl4 (l) + 2Mg(s)
Ti(s) + 2MgCl2 (s)
This reaction falls under the category of Displacement reactions.
(e) CaO(s) + SiO2(s)
CaSiO3(s)
This is a synthesis reaction.


(f) 2H2O2 (l) ⎯⎯⎯⎯ UV 2H2O(l) + O2 (g)
This is a decomposition reaction.


Note:
A synthesis reaction is a chemical reaction in which multiple reactants combine to form a single product.
A decomposition reaction is a type of chemical reaction in which a single reactant breaks down into two or more elements or chemical compounds. If this decomposition is brought about by heat, then it is termed as thermal decomposition.
Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound.


35
1