Question

Given the equation below, What is the reducing agent?

NOTE: Only enter the element symbol. For instance: K, or Cr, or
O, or H.
K2Cr2O3 + H2O + S --> SO2 + KOH + Cr2O3

Answer 1

Reducing agent - S

Step-by-step explanation:

The equation for the reaction is given as;

K2Cr2O3 + H2O + S --> SO2 + KOH + Cr2O3

The balanced equation is given as:

2K2Cr2O7 + 2H2O + 3S → 3SO2 + 4KOH + 2Cr2O3

The reducing agent can be obtained by comparing the oxidation number of the elements. Increase in oxidation number signifies a reducing agent

K:

Reactant - 1

Product - 1

Cr

Reactant - +2

Product - +3

O

Reactant - -2

Product - -2

H

Reactant - +1

Product - +1

S

Reactant - O

Product - +4

S has an increase in oxidation number hence it is the reducing agent.

Although Cr has an increase in oxidation number, it occurs as a compound.