Question

What is the mass of `4.75 * 10^21` platinum atoms?

Answer 1

`1.54g`

Explanation:

`6.023xx10^23` Pt atoms constitutes `1` mole of Pt.

Hence, by ratio and proportion, `4.75xx10^21` atoms constitutes `0.0078864` moles.

Hence the mass will be the product of the moles with the molar mass,

`m=nxxM_r`

`=0.0078864molxx195.1g//mol`

`=1.54g`.