Question

What is the mass in grams of a sample of 1.20×1022 exponent atoms of mercury

Answer 1

For this problem, we are going to be using multiplication and cancelling units. We need to first find the molar weight of mercury, found on the periodic table as 200.59g/mol.

So then we set up the equation:


`(1.20* 10^(22)atoms )/(1)* (1mole)/(6.022* 10^(23)atoms ) * (200.59gHg)/(1mole)`


Then we multiply straight across to find the mass in grams:



`(1.20* 10^(22)atomsHg )/(1)* (1 mole)/(6.022* 10^(23)atoms ) * (200.59g)/(1mole) = 3.99g Hg`

So now we know that the mass of this sample is 3.99g Hg.