Question

Question #1d3d1

Answer 1

x = 7 Solution follows

Explanation:

From the formula, we can see that the number of oxygen atoms would be 4 + x. The total mass of this oxygen would then be `16 xx (4+x) = 64 + 16x`

In the same way, the mass of the entire compound can be expressed in terms of x, as

`(24.3 + 32.1 + 64.0) + x(2+16)= 120.4+18x`

The fraction of the mass that is oxygen is therefore

`(64 + 16x)/(120.4+18x)`

and because we know the oxygen represents 71.4% of the mass, we can write

`(64 + 16x)/(120.4+18x)=0.714`

Now, solve for x:

`64 + 16x=(120.4+18x)xx0.714`

`64 + 16x=85.97+12.85x`

`3.15x = 21.97`

`x=6.97` which we round off to 7