How do you balance Li + CO2 + H20 → LiHCO3 + H2

Answer 1

All the elements are ok except H, with 2 on the left but 3 on the right side.

Double the H2O to get 4 on the left side. Now you need a 4th H on the right side, so double the LiHCO3

That balances H, but you need to double the Li on the left side Also you need more C on the left so double the CO2. That balances H, Li, C, and O

Just double everything in the original reaction, except for the H2 on the right. That balances the reaction,

with 2Li on both sides

2C on both sides

6O on both sides

and 4H on both sides

Either do trial and error, or if you know matrix algebra there's another way to always find the solution. Just translate it into matrices.