8. The mass of NaOH required to prepare 250~cm^{3} of 0.1M NaOH is (A) 10g (B) 4g (C) 40g (D) 1g
To find the mass of NaOH required, we can use the formula:
mass = concentration x volume
The concentration is given as 0.1M, and the volume is given as 250 cm^3.
mass = 0.1M x 250 cm^3 = 25g
Therefore, the correct answer is (E) 25g.