Question

Calculate the mass of 0.5 mole of N atoms.

Answer 1

The Avogadro number is defined as the number of molecules which are present in 1 mole of the substance which is equal to $6.023\times {{10}^{23}}$atoms in the substance. The Avogadro number is denoted by ${{N}_{A}}$. The value given above can be used directly to calculate the number of atoms present in different representational units.

Complete step-by-step solution: to calculate the mass of 0.5 moles of nitrogen we should know the atomic mass of the element nitrogen. As we know that the mole of the element given is equivalent to the given mass which is further divided by the total mass. So to find the mass on simplifying we get the below formula
Mass= number of moles x molar mass
We also know by mole concept that
1g atom= 1 mole atom and,
We know the atomic mass of nitrogen atom is 14g/mol
$mass=0.5\times 14$
$\Rightarrow mass=7g$
So the mass of 0.5 mole of nitrogen atom is 7g. $\Rightarrow mass=7g$
Below are some standard terms which are used in mole concept
1 gram molecule = 1 mole of molecule
1 gram ion = 1 mole ion
1 gram atom = 1 mole atom

Hence the mass of 0.5 moles of nitrogen atom is 7g.

Note: Mole is not only related to mass but also related to volume. The relation between the two is that 1mole of substance= 22.4L of volume of the substance= 22400mL of the substance. Nitrogen is used in the manufacture of ammonia and nitric acid. Liquid nitrogen is used as the refrigerant and in preservation of reproductive cells.