Question

Show the dissociation of the following compounds on dissolving in water, with the help of chemical equation and write whether the proportion of dissociation is small or large.
Hydrochloric acid, Sodium chloride, Potassium hydroxide , Ammonia , Acetic acid , Magnesium chloride, Copper sulphate .

Answer 1

i) Hydrochloric acid when dissolved in water

$HCl+H_{2}O\to H_3{O}^{+}+C{l}^{-}$

The properties of reaction is large and dissociates completely in water.

ii) Sodium chloride when dissolved in water

$NaCl+H_{2}O\to N{a}^{+}+C{l}^{-}$

It will completely dissolves in water and no chemical reaction occurs because water is highly polar.

iii) Potassium hydroxide when dissolved in water

$KOH+H_{2}O\to K^{+}+O{H}^{-}$

When potassium hydroxide dissolves in water a small change occurs, it dissociates into potassium ion and hydroxide ion.

iv) Ammonia when dissolved in water

$N{H}_3+H_{2}O\to O{H}^{-}+N{H}_4^{+}$

Ammonia dissolves into water readily to give ammonium ion and hydroxide ion.

v) Acetic acid when dissolved in water

$C{H}_{3}COOH+H_{2}O\to C{H}_{3}CO{O}^{-}+H_3{O}^{+}$

When acetic acid dissolves in water it gives hydronium ion and acetate ion. Large dissociation occurs.

vi) Magnesium chloride when dissolved in water

$MgC{l}_2+H_{2}O\to M{g}^2++C{l}^{-}$

When magnesium chloride dissolves in water it gives magnesium and chloride ions. So the resulting solution is ionized.

vii) Copper sulphate when dissolved in water

$CuS{O}_4+H_{2}O\to C{u}^2++S{O}_4^2-$

When copper sulphate is dissolved in water it gives copper and sulphate ions and small amount of energy is released.