since you are requesting for ion it will be cr^3 as if you look it then OH has -1 charge since there are 3 of them soo to neutralise it we need 3 Cr ion hence answer will be cr^3+

Cr(OH)3 (Chromium(III) hydroxide) is a compound with three hydroxide ions (OH-) and one chromium ion (Cr3+). ClO- (hypochlorite ion) is a negatively charged ion with one chlorine atom and one oxygen atom. OH- (hydroxide ion) is a negatively charged ion with one oxygen atom and one hydrogen atom. Cl- (chloride ion) is a negatively charged ion with one chlorine atom. H2O (water) is a molecule with two hydrogen atoms and one oxygen atom.

To determine the missing ion in the reaction, we need to balance the charges on both sides of the chemical equation. Let's analyze the charges:

On the left side of the equation:
- Cr(OH)3 has a net charge of 0 since the chromium ion (Cr3+) has a charge of 3+ and there are three hydroxide ions (OH-) with a charge of 1- each.
- ClO- has a charge of 1-.

On the right side of the equation:
- OH- has a charge of 1-.
- Cl- has a charge of 1-.
- H2O has a net charge of 0 since water is a neutral molecule.

Now, let's balance the charges:

On the left side, the total charge is 0 (Cr(OH)3 + ClO-).
On the right side, the total charge is also 0 (OH- + Cl- + H2O).

Since both sides of the equation have a net charge of 0, it means that the missing ion must also have a charge of 0.

The missing ion in the reaction is H2O (water).