Question

You are given a sample contains 0.40 moles of a substance. How many samples are in the atom if the substance is zinc?

Answer 1

1 mole zinc ----------------- 6.02 x 10²³ molecules
0.40 moles zinc ----------- ( molecules zinc )

molecules zinc = 0.40 x ( 6.02 x 10²³) / 1

molecules zinc = 2.40  x 10²³ / 1

= 2.40 x 10²³ molecules of zinc

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