2Ce(IO3)4(aq) + 24H2C2O4(aq)→Ce2(C2O4)3(aq) + 4I2(aq) + 42CO2(g) + 24H2O(l)

What would it look like if Decrease the volume.

rewrite the equation

There is no need to rewrite the equation as decreasing the volume does not change the chemical formula or reaction involved. However, it may affect the concentration of the reactants and products, which could impact the rate of the reaction and the direction of the equilibrium.