Question

What mass of `"potassium chlorate"` is required to produce a `2.24*L` volume of dioxygen gas at `"NTP"`?

Answer 1

We need (i) a stoichiometric equation, and (ii)......

Explanation:

and........(ii) we need the molar volume at `NTP`, which I think is `24.04*L*mol^-1`.......

Now as regards (i)......

`KClO_3(s) + Delta stackrel(MnO_2)rarrKCl(s) + 3/2O_2(g)uarr`

The reaction generally works well if you add some `"manganese (IV) oxide"` as an oxygen transfer reagent.

And so moles of dioxygen gas......`=(2.24*L)/(24.04*L*mol^-1)`

`=0.0932*mol`

And so the molar quantity of `KClO_3` is......

`2/3xx0.0932*molxx122.55*g*mol^-1=7.61*g`.

Look at the question again, are you sure that it did not ask for `"STP"`? The different definitions and standards vary across each syllabus; there are different definitions in yurope, Blighty, and the States. So you need to look up your definition of `"NTP"`.