Question

What is the percent composition of sodium sulfate, Na2SO4?

Answer 1

Approx...`33%`

Explanation:

We take the quotient....

`"Mass of sodium"/"Mass of material"xx100%`...and we work out the quotient on a basis of a mole of sodium sulfate, i.e. `142.04*g*mol^-1`.

And so... `underbrace(2xx22.99*g*mol^-1)_("mass of sodium")/underbrace(142.04*g*mol^-1)_"molar mass of salt"xx100%=??%`

Answer 2

See the below;

Explanation:

Well, I don't think the question has any hard crack, cause we are finding the whole composition for the element it self.

Except if you mean; **What is the composition of sodium `(Na)` in sodium sulphate `(Na_2SO_4`

But since its not stated, we will find the whole composition which is actually `100%` in total..

`"Sodium sulphate" = Na_2SO_4`

It has the following compositions;

`32.37% = Na`

`22.57% = S`

`45.06% = O`

Or

`32.37% = Na`

`67.63% = SO`

Hence;

`Na_2SO_4 = 100%`