Calculate
(a) mass of 1.5 gram atoms of calcium (at. mass = 40)
(b) gram atoms in 12.8 g of oxygen (at. mass = 16)

Explanation

(a) 1 gram atom of calcium = 40 g
1.5 gram atoms of calcium = 40 x 1.5 = 60 g
(b) 1 gram atom of oxygen = 16 g
16 g of oxygen = 1 gram atom
12.8 g of oxygen `=1/16 xx 12.8`
=0.8 gram atom