Calculate the number of atoms in a 1.74 x 10^3 g sample of calcium

Question

Calculate the number of atoms in a 1.74 x 10^3 g sample of calcium

Answer 1

Hey Matelie.

The first step is to understand that you can convert grams of calcium to moles of calcium then to number of atoms of calcium.

The molar mass of Calcium is 40.078 g/mol

Canceling out our units we can convert the 1.74x10^3 g to moles.

1.74x10^3g/ 40.078g/mol = 43.42 moles of calcium

Now use Avogadro's number to calculate the number of atoms. (6.022X10^23)

43.42 moles x 6.022X10^23 atoms/mole = 2.61x10^25 atoms of Calcium.

If you need more help, feel free to reach out.

John