Question

Calculate the mass of sodium hydroxide required to prepare 100gm of 20% w/w solution in water

Answer 1

Answer:

20 grams of NaOH

Explanation:

w/w solution means: $\frac{mass of NaOH }{mass of solution}$

Here 20% means that 20gms of NaOH in 100 gms of solution.

So simply add 20 grams of NaOH to 80 gms of water and voila!!