A solution of sodium carbonate of concentration 0.100moldm-3 is used to standardize a solution of hydrochloric acid. 25cm3 of the standard solution of sodium carbonate require 35cm3 of the acid for neutralization. Calculate the concentration of the acid.

Answer 1

Na2CO3 + 2HCl ==> 2NaCl + H2O + CO2
mols Na2CO3 used = M x L = 0.100 x 0.025 L = ?
mols HCl needed = 2 x mols Na2CO3 (from the coefficients in the balanced equation.
M HCl = mols HCl/0.035 L= ?