Question

How many atoms are present in 9.0 gram of aluminium

Answer 1

Answer:

Answer:

2.00 \times 10^{23}2.00×10

23

atoms are present in 9 gram of aluminium.

Explanation:

‘Molecular or molar mass’ of the element is the “mass of one mole” of an element =6.022 \times 10^{23}=6.022×10

23

atoms.

The molecular mass of aluminium = 27g

Number of moles = Mass of the given substance / mass of one mole

N =\frac{9}{27}=

27

9

= 0.333 mol.

To convert the moles into atoms, the number of moles calculated should be multiplied by the molecular mass of ‘one mole of the element’ or the Avagadro’s number, 6.022 \times 10^{23}6.022×10

23

atoms.

So the number of atoms in 9.0 g of aluminium =0.333 \times 6.022 \times 10^{23}=0.333×6.022×10

23

atoms.

=2.00 \times 10^{23}=2.00×10

23

atoms.