1.
125mL125\,\text{mL} of 63%63\% (w/v) H2C2O42H2O\mathrm{H_2C_2O_4 \cdot 2H_2O} solution is made to react with 125mL125\,\text{mL} of a 40%40\% (w/v) NaOH solution. The resulting solution is (ignoring hydrolysis of ions):