Write a balanced half-reaction for the reduction of dichromate ion cr2o−27 to chromium ion cr 3 in basic aqueous solution. be sure to add physical state symbols where appropriate.

Explanation:

When electrons are added in a reaction then it means reduction is taking place. Whereas removal of electrons from a chemical reaction is known as oxidation.  

Oxidation state of chromium in is +6. So, its reduction half-reaction will be as follows.

Since it is given that reaction is taking place in basic solution. So, we add on reactant side and on the product side.

Now balancing Cr atom and charges on both sides, we get the following.

the ratio of the conjugate base to the acid required to attain the desired ph.