Question

In analyzing the crude fiber content of a certain food, 0.313N NaOH is required. What is the mass of NaOH pellets needed to prepare 500ml of the solution? What is the molarity of the solution?

Answer 1

$$f(NaOH) = 1$$

Then:

$$c_N(NaOH) = c(NaOH) = 0.313M$$

$$n(NaOH) = c(NaOH)V(NaOH)$$

$$n(NaOH) = 0.313M*0.5L = 0.1565mol$$

$$m(NaOH) = nM = 0.1565mol*39.997g/mol =6.2595g = 6.26g$$

ANSWER: 0.313M; 6.26g