This is an oxidation-reduction (redox) reaction
2 HI + 2 e- → 2 H0 (reduction)
Ca0 - 2 e- → CaII (oxidation)
HClO4 is an oxidizing agent, while Ca is a reducing agent.
Word equation
Calcium + perchloric acid → calcium perchlorate + hydrogen
Input interpretation
Ca + 2HClO4 → Ca(ClO4)2 + H2
Balanced equation
Ca + 2HClO4 → Ca(ClO4)2 + H2
To balance the equation, stoichiometric coefficients are added to the reactants and products. The number of atoms of each element on both sides of the equation should be equal.
c1 Ca + c2 2HClO4 → c3 Ca(ClO4)2 + c4 H2
Ca: c1 = c3 Cl: c2 = 2c3 H: 2c4 = c2 O: 4c2 = 8c3
Choosing an arbitrary coefficient value of 1 for c1, the remaining coefficients are solved using the system of equations:
c1 = 1, c2 = 2, c3 = 1, c4 = 1
Substituting the coefficients back into the balanced equation yields:
Ca + 2HClO4 → Ca(ClO4)2 + H2
This reaction shows the reaction between calcium and perchloric acid, producing calcium perchlorate and hydrogen gas.