Question

Could you please Calculate the number of atom of 40K (potassium 40) in 1gram of KCl. Taking into account the isotopic abundance of 40K that is 0.0118%)

Answer 1

Answer:

$9.53*10^{17}$ atoms of 40K

Explanation:

You can use the molecular mass and the Avogadro´s number, in the following formula:

$N_{40K=\frac{m_{KCl}}{M_{MKCl}}}*N_{Avogadro}*(IA_{40k})$

where $m_{KCl}$ is the sample mass, $M_{KCl}$ is the molecular mass of the KCl and IA(40K) is the isotopic abundance of 40K.

Now replacing the values, you can find:

$N_{40K}=\frac{1g}{74.5513\frac{g}{mol}}*6.022*10^{23}mol^{-1} *0.000118$

$N_{40K}=9.53*10^{17} atoms$