In the reaction,

K2Cr2O7 +14 HCl ----> 2KCl + 2CrCl3 + 3Cl2 + 7H2O
how many moles of HCl act as reducing agent in balanced chemical equation?

The Cl going to 2KCl and the Cl going to 2CrCl3 aren't reduced. The only Cl^- reduced are those going to 3Cl2 so 6HCl ==> 3Cl2.

To determine how many moles of HCl act as the reducing agent in the given balanced chemical equation, you need to consider the stoichiometry of the reaction. The coefficients in a balanced equation represent the ratio of moles of reactants and products.

In this reaction:

K2Cr2O7 + 14 HCl → 2 KCl + 2 CrCl3 + 3 Cl2 + 7 H2O

The coefficient of HCl is 14, which means that for every mole of K2Cr2O7, you need 14 moles of HCl to completely react.

Therefore, in the balanced chemical equation, 14 moles of HCl act as the reducing agent.