question_answer

                               What is the mass of (a) 0.2 mole of oxygen atoms? (b) 4 mol of aluminium atoms (Atomic mass of aluminium = 27)? (c) 10 mol of  (sodium sulphite)? (d) 1.50 mol of  ion? 

Answer:

                    (a) 1 mole of oxygen atom = 16 g 0.2 mole of oxygen atom == 16 x 0.2 == 3.2 g (b)   1 mol of Al == 27 g 4 mol of Al == 27x4 == 108 g. (c)   1 mol of  [23 x 2 + 32 +16 x 3] = 126 g 10 mol of = 126 x 10 = 1260 g. (d)   1 mol Na + ions = 23 g 1.50 mol of Na+ ions == 23 x 1.50 = 34.5 g