Question

you are given a sample containing 0.70 moles of a substance. How many atoms are in the sample if the substance is zinc?

Answer 1

1 mole ------------- 6.02 x 10²³ atoms
0.70 moles -------- ( atoms zinc )

atoms platinum = 0.70 x ( 6.02 x 10²³ ) / 1

= 4.2 x 10²³ atoms zinc

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