Question

The sun is composed mostly of hydrogen. The mass of the sun is 2.0x10^30 kg, and the mass of a hydrogen atom is 1.67x10^-27 kg. Estimate the number of atoms in the sun.

Answer 1

We assume that the sun is all hydrogen for this or the amount other components are negligible. The calculations are as follows:


2.0x10^30 kg of sun x ( 1.67x10^-27 kg hydrogen atom / 1 kg of sun ) = 3340 kg hydrogen atom

3340 kg hydrogen atom ( 1000 g / 1 kg ) ( 1 mol H/ 1.01 g H ) = 3306930.693 mol H 

3306930.693 mol H x (6.022 x 10^23 atoms / 1 mol ) = 1.99 x 10^30 atoms H

Answer 2

Answer: The number of hydrogen atoms in Sun is $1.2\times 10^{57}$

Explanation:

We are given:

Mass of Sun = $2.0\times 10^{30}kg$

Mass of hydrogen atom = $1.67\times 10^{-27}kg$

To calculate the number of hydrogen atoms, we divide the mass of Sun to the mass of hydrogen atom, we get:

$\text{Number of hydrogen atom}=\frac{\text{Mass of Sun}}{\text{Mass of hydrogen atom}}$

Putting values in above equation, we get:

$\text{Number of hydrogen atoms}=\frac{2.0\times 10^{30}kg}{1.67\times 10^{-27}kg}=1.2\times 10^{57}$

Hence, the number of hydrogen atoms in Sun is $1.2\times 10^{57}$