6.2.1 - Reversible reactions

Question 1

What are reversible reactions?

Answer 1

Ones where the products of the reaction can react to reform the original reactants.

Question 2

How are reversible reactions represented?

Answer 2

A+B⇌C+D

Question 3

How can the direction of reversible reactions be changed?
Give an example

Answer 3

By changing the conditions of the reaction

e.g. Heating ammonium chloride produces ammonia and hydrogen chloride gases

ammonium chloride(s) → ammonia(g) + hydrogen chloride(g)

As the hot gases cool down they recombine to form solid ammonium chloride

This is an exothermic process

ammonia(g) + hydrogen chloride(g) → ammonium chloride(s)

So, the reversible reaction is represented like this:

NH4Cl (s) ⇌ NH3 (g) + HCl (g)