Question

Calculate the number of atoms in 4g of hydrogen

Answer 1

Answer:

4 × 6.02 10²³ atoms

Explanation:

Given the weight of hydrogen taken is 4g

we know that,

the atomic mass of hydrogen = 1 g

no of moles of hydrogen = Given mass/atomic mass

                                          = 4/1 = 4 moles

no of atoms = no of moles × Avagadro Number

                    = n × N

                    = 4 × 6.02 × 10²³ atoms

Answer 2

$\huge\red{\bold{\underline{\underline{Solution:-}}}}$

Number of grams of hydrogen = 4g

Atomic weight of hydrogen = 1

$\small\rm{\bold{\boxed{Number\:of\:moles\:=\:\frac{Given\:weight}{gram\:atomic\:weight}}}}$

$\large\rm{\rightarrow{Number\:of\:moles\:=\:\frac{4}{1}}}$

$\large\rm{\rightarrow{Number\:of\:moles\:=\:4}}$

1 mole of any substance contains 6.023 × 10²³ atoms

By unitary method ,

If 1 mol --------------> 6.023 × 10²³

4 mol ---------------> 'x' (let)

$\large\rm{\rightarrow{x\:=\:\frac{6.023\times\:{10}^{23}\times\:4}{1}}}$

$\large\rm{\rightarrow{x\:=\:24.092\times\:{10}^{23}}}$

∴ Number of atoms in 4g of hydrogen is 24.092 × 10²³