Question

Calculate the mass of 2.5-gram atoms of oxygen.

Answer 1

Gram atomic mass:

1. The gram atomic mass of a compound defines the mass of 1 mole of that substance.
2. We can also say the gram atomic mass is the total mass of all the atoms in grams that make a mole of atoms.

Given

1. The gram atomic mass of oxygen = 16g/mole
2. We can say the mass of 1 mole of Oxygen = 16g
3. Number of atoms of Oxygen in 1 mole = 6.022 x 10²³
4. We can say the mass of 6.022 x 10²³ atoms of Oxygen is 16g
5. $\mathrm{Number}\mathrm{of}\mathrm{grams}\mathrm{of}\mathrm{Oxygen}\mathrm{atoms}=\frac{\mathrm{Mass}}{\mathrm{Atomic}\mathrm{Mass}}$
6. $2.5\mathrm{g}\mathrm{of}\mathrm{Oxygen}\mathrm{atom}=\frac{\mathrm{Mass}}{16}$
7. $\mathrm{Mass}=40\mathrm{g}$

Therefore, the mass of 2.5-gram atoms of oxygen is 40g.