Question

What ia the effect of change of ph on dicromates ion intext:zigya?

Answer 1

The dichromate ion(Cr2O72-) exists in equilibrium with chromate(CrO42-) ion at pH 4, However by changing the pH, they can be inter converted.

Effect of decrease in pH

chromate (yellow)-------->dichromate(orange)

2CrO42- + 2H+ → Cr2O72-+ H2O

Effect of increase in pH

dichromate(orange)--------------->chromate (yellow)

Cr2O72-+ 2OH- → 2CrO42- + H2O