When six  ${\text{CO}}_{\text{2}}$ molecules are fixed to produce one glucose in  ${\text{C}}_{\text{3}}$ plant, how many chemical intermediates are used in reduction phase ?

12 ATP and 12 NADPH are utilized to reduce 6 ${\text{CO}}_{\text{2}}$  in reduction phase of calvin cycle. Total 18 ATP and 12 $NADP{H}_2$  are utilized to produce 1 glucose in Calvin cycle.