Question

4.6 × 10²² atoms of an element weighs 13.8 g. The atomic weight of that element is

(a) 290

(b) 180

(c) 34.4

(d) 10.4

Answer 1

Correct option is (b) 180

4.6 × 10²² atoms weigh = 13.8 g

Hence, 6_·02 × 10²³ atoms will weigh = \(\frac{13.8 \times 6.02 \times 10^{23}}{4.6 \times 10^{22}}\)

= 180.6 g (molar mass)