Question

1. What type of reaction is listed below? Prove that it is balanced by listing the number of elements on both side of the equation (reactants vs. products)? CH3COOH + NaHCO3  NaCH3COO + H2CO3

Answer 1

is there a mistake or am i doing something wrong  

Answer 2

It is a double replacement, followed by a decomposition.

NaHCO3(aq) + CH3COOH(aq) → CH3COONa(aq) + H2CO3(aq) (double replacement)
H2CO3(aq) → H2O(l) + CO2(g) (decomposition)

The decomposition is so fast that you have no measurable concentration of H2CO3 in the solution. The formation of CO2 forms the bubbles in the solution.