Question

how many moles are there in 8.1 gram of aluminium​

Answer 1

 

Solution :

The weight of one mole of a substance is equal to its atomic mass in grams , therefore

1 mole of Al =27g=27g of Aluminium

Also , 1 mole contains Avogadro number of atoms

1mole=6.023×10231mole=6.023×1023 atoms of Aluminium

Therefore

1 mole of Al - 27 g of aluminium - 6.023×10236.023×1023 atoms of aluminium

Number of atoms in 8.1g8.1g aluminium is =(8.1×6.023×1023)/27=(8.1×6.023×1023)/27

The face centered cubic structure contains 4 atoms in one unit cell .

Therefore , the number of unit cells that has (8.1×6.023×1023)/27(8.1×6.023×1023)/27atoms of Aluminium can be obtained as ,

(8.1×6.023×1023)/(27×4)=4.516×1022

Answer 2

Answer:

.3moles

Explanation:

no of moles=given wieght÷original.

weight

=8.1÷27

=.3moles