Question

Calculate the formula mass for the compound tin(IV) sulfate.

Answer 1

Hi there, the formula should be Sn(SO4)2
Since the formula mass is just the sum of all atomic weights of the atoms in its empirical formula (which it already is), you just need to add them together given that:
Molecular Mass (Sn): 118.7
Molecular Mass (S): 32.07
Molecular Mass (O): 16

Answer 2

I got up to the point where I figured out Sn(SO4)2 and I also did this:
118.71+32.07+(16x8) = 278.78
The answer was wrong though, I don't understand what I did wrong.

Answer 3

Ah, you forgot to multiply the molecular mass of SO4 by two.

Answer 4

I multiplied 4x2 to get 8 & multiplied 8 by 16.00.

Answer 5

But you didn't do it for the sulfur

Answer 6

Oh you mean multiplying the molecular mass of Sulfur by 2 right?

Answer 7

Yup! =D

Answer 8

Thanks! I don't know how I missed that!

Answer 9

Don't worry! I do that too!