How many atoms are in 8.00 moles of potassium chromate?

Explanation:

To convert from moles to atoms, Avogadro's Number must be used.

This number tells us how many particles (atoms, molecules, ions. etc.) in 1 mole of a substance. In this case, it is atoms of potassium chromate (K₂CrO₄) in 1 mole.

Use this number as a fraction.

Multiply by the given number of moles (8.00).

The moles of potassium chromate will cancel.

The denominator of 1 can be ignored.

Multiply.

The original measurement of moles (8.00) has 3 significant figures, so we must round our answer to 3 sig figs.

For the number we calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 1 up to a 2.

There are about 4.82* 10²⁴ atoms of potassium chromate in 8.00 moles.