Question

How many grams is 2.393 x 10^24 atoms of O?

70.45 g O
140.9 g O
63.58 mole O
63.58 g O

Answer 1

63.58 g O

Step-by-step explanation:

To calculate the mass of O atoms, the number of moles of O atoms are needed and can be calculated as follows:

n (no. of moles) = nA ÷ 6.02 × 10^23

n = 2.393 x 10^24 ÷ 6.02 × 10^23

n = 0.398 × 10^ (24-23)

n = 0.398 × 10^1

n = 3.98moles.

To calculate the mass of Oxygen, we use the following formula:

moles = mass/molar mass

Molar mass of O = 16.

3.98 = m/16

m = 3.98 × 16

m = 63.68grams of Oxygen.

Answer 2

Solution given:

`1 mole \:of O=6.023×10^(23) atoms`

1 mole of O =16g

we have

`6.023×10^(23) atoms\: of O=16g`

now

`2.393 × 10^(24) atoms\: of \:O\\=16/6.023×10^(23)*2.393 x 10^(24)g\\=63.57g`

63.57g is a required mass of O.