Question

Question #3ff32

Answer 1

`"Option ..........B"`

Explanation:

We simply need to find the molar quantity of sulfuric acid.........and multiply this molar quantity by Avogadro's number.............and then perform the subtraction.

`"Moles of stuff"="Mass of stuff"/"Molar mass of stuff"`

And here `"Moles of sulfuric acid"=(98xx10^-3*g)/(98.08*g*mol^-1)`

And so number of sulfuric acid molecules...........

`=N_Axx(98xx10^-3*g)/(98.08*g*mol^-1)`

`=6.022xx10^23*mol^-1xx(98xx10^-3*g)/(98.08*g*mol^-1)=6.0xx10^20` `"molecules"`. And if we take `3xx10^20` molecules away from this quantity we are left with `3xx10^20` such molecules.

And this represents a molar quantity of `(3xx10^20*"molecules")/(6.022xx10^23*"molecules"*mol^-1)=5xx10^-4*mol`.

Not a good question, in that they are simply asking you how to use a calculator. This is non-trivial but also non-chemistry.