Question

Calculate the mass of 0.75 moles of CaSO4 ( atomic mass; Ca = 40 u, S =32 u, O = 16 u)

Answer 1

Explanation:

(a) Calculate its molarity. (b) What is the concentration in grams per L? (a) moles = mass / molar mass, (KBr = 39.1 + 79.9 = 119 g /mol).

Answer 2

Answer: 102 u

Explanation:

Molar mass of CaSO4 will be

40 + 32 + (16x4) = 136

Therefore mass of 1 mole of compound is 136 u

Mass of 0.75 moles will be 0.75x136 u

i.e 102u

This is your required answer.