Question #90e5d

1 Answer
Dec 5, 2014

I gave this a go and I got a number close to 50%.

Let us name the two compunds XOA and XOB.

We know that the ratio of some element, let us say X, to oxygen in XOA is 1:0.29.

That is, for every 1g of X we have 0.29g of OA. (1)

Now, taking into account the oxygen-to-oxygen ratio between XOA and XOB is 2:7, we can say that

for every 2g of OA we have 7g of OB (2) or, for simplicity, for evey 1g of OA we get 3.5g of OB.

Therefore, using (1) and (2), we can say that

for every 1g of X we have 0.293.5g=1.02g OB for the second coumpound.
An approximately 1:1 ratio of X and OB in XOB means that the percent composition of X to XOB is

percentcomposition=11+1100=50%