Question

7. What is the mass of-
(a) 1 mole of nitrogen atoms?
(b) 4 moles of aluminium atoms (Atomic mass of aluminium
= 27)?
(c) 10 moles of sodium sulphite (Na, SO)?​

Answer 1

Answer:

(a) 1 mole of nitrogen atoms=1×mass of N=1×14=14 g

(b) 4 moles of aluminium atoms=4×27=108 g

(c) 10 moles of sodium sulphite(Na

2

SO

3

)=10×Mass of Na

2

SO

3

.

Mass of Na

2

SO

3

=2×Mass of Na atom+1×Mass of S atom+3×Mass of O atom

=2×23+1×32+3×16=46+32+48=126 g/mol

∴10 moles of Na

2

SO

3

=10×126=1260 g

Answer 2

Answer:

a) Mass of 1 mole of nitrogen atoms = 14g

b) mass of 4 moles of aluminium atoms = 108g

c) Mass of 10 moles of sodium sulphite = 1260g