Elemental mercury was first discovered when a mercury oxide was decomposed with heat, forming mercury metal and oxygen gas. When a 0.204-g sample of the mercury oxide is heated, 0.189 g of mercury metal remains.

a)what is mole ratio of mercury to oxygen in the sample?

would it be

0.204 g x mol Hg/200.59= 0.001

0.189 g x mol Hg/200.59= 9.422204497E^-4

am confused don't know how to solve further.

&

b) what will be the empirical formula for mercury oxide?

please help thnk :)

3 answers

HgO ==> Hg + O2
0.204...0.189..0.015
Remember the law of conservation of mass. The stuff on the right must add up to the stuff on the left.
Your mol Hg is correct at 0.000942
mol O2 = 0.015/32 = 0.000469
Then 0.000942/0.000469 = 2.008 which rounds to 2Hg to 1 oxygen.
So the ratio of mercury to oxygen will be 2:1 and how can find the empirical formula please...thank you
The ratio of Hg to O2 is 2:1.
The ratio of Hg to O(atom) is 1:1
Formula is HgO.
0.189/0.000942
0.150/16 = 0.00094375
ratio is 1:1 formula HgO.