Question

What's the sodium hydroxide solution is standardized using 0.502 g of solid acid H2C2O4. Find the molarity of the base if 30.50 mL are required for the titration to a phenolphthalein endpoint?

Answer 1

Answer to Question #49691, Chemistry, Inorganic Chemistry

What's the sodium hydroxide solution is standardized using 0.502 g of solid acid H₂C₂O₄. Find the molarity of the base if 30.50 mL are required for the titration to a phenolphthalein endpoint?

Solution:

$$\mathrm{H_2C_2O_4} + 2\mathrm{NaOH} \rightarrow \mathrm{Na_2C_2O_4} + 2\mathrm{H_2O}$$ $$c = \frac{n}{V}$$ $$n(\mathrm{NaOH}) = 2 \times n(\mathrm{H_2C_2O_4}) = \frac{2 \times m(\mathrm{H_2C_2O_4})}{M_r(\mathrm{H_2C_2O_4})}$$ $$c = \frac{2 \times m(\mathrm{H_2C_2O_4})}{M_r(\mathrm{H_2C_2O_4}) \times V}$$ $$c = \frac{2 \times 0.502}{90 \times 0.0305} = 0.366 \ \mathrm{mol/L}$$

Answer:

0.366 M

https://www.AssignmentExpert.com