Question

The number of molecules of Oxygen in 1 litre of air (21% of oxygen by volume) at STP would be
a) 5.65 x 1021
b) 5.65 x 1025
c) 5.65 x1022
d) 5.65 x 1020 ​

Answer 1

Answer:

5.65×10²¹

Explanation

1 mole of oxygen contains 22.4 litres it contains 6.023×10²³

Then 21 × 6.023×10²³÷100

That is equal to 5.65 × 10²¹