Question

What is the molarity of potassium ions in a 0.122 M K2CrO4 solution

Answer 1

 The molarity   of potassium  ions  in a 0.122 M  K2CrO4  is 0.244 M

Explanation

write dissociation reaction  for K2CrO4

that  K2CrO4 (aq)→ 2K^+ (aq)  + CrO4^2- (aq)

K2CrO4  dissociate to give  2  ions of potassium ,therefore  the molarity  of potassium ion = 2 x 0.122  = 0.244 M

Answer 2

Answer : The molarity of potassium ions in a $K_2CrO_4$ solution is 0.244 M

Explanation :

The dissociation reaction of $K_2CrO_4$ in solution will be:

$K_2CrO_4\rightarrow 2K^++CrO_4^{2-}$

From the reaction we conclude that, 1 mole of $K_2CrO_4$ dissociate in solution to give 2 moles of $K^+$ ion (potassium ion) and 1 mole of $CrO_4^{2-}$ ion (chromate ion).

As per question,

0.122 M of $K_2CrO_4$ dissociate in solution to give $2\times 0.122M=0.244M$ of $K^+$ ion (potassium ion) and 0.122 M of $CrO_4^{2-}$ ion (chromate ion).

Hence, the molarity of potassium ions in a $K_2CrO_4$ solution is 0.244 M