Question

How many grams of `O` are contained in 8.52 g `K_2CO_3`?

Answer 1

In 1 mole of potassium carbonate there are clearly 3 moles of oxygen atoms (i.e. 48.00 g), almost half the mass of 1 mol of the salt.

Explanation:

Moles of `K_2CO_3` `=` `(8.52*g)/(131.21*g*mol^-1)` `=` `??` `mol`.

But there are 3 mol of oxygen in each mole of `K_2CO_3`.

So moles of oxygen `=` `3xx(8.52*g)/(131.21*g*mol^-1) = ?? mol`.