Question

results for Mass of 2 ×10^21 number of atoms of an element is 0.4g what is the mass of 0.5 mole of the element

Answer 1

Explanation:

2*10²¹ atom means 0.02*10²³ also.

0.02*10²¹ atom = 0.4 gm

mass of one atom = 0.4/0.02*10²³

then

mass of 0.5 mole means mass of 3*10²³ atom(taken one mole = 6*10²³ atom)

mass of 3*10²³ atom = 0.4*3*10²³/0.02*10²³ = 60gm

mass of 0.5 mole = 60 gm