Question

`"Sodium azide"`, `NaN_3`, is used in automobiles to fill air bags: (i) is this an example of chemical change; (ii) is the mass of the products equal to the mass of the reactants; and (iii) could a `83.0*g` sodium azide give rise to a volume of `36*L`?

Answer 1

Yes, yes, yes....

Explanation:

So we gots....

`2NaN_3(s) rarr 2Na(s) + 3N_2(g)`

We could separate this reaction out into half equations...

`underbrace(Na^(+) + e^(-) rarr Na(s))_"reduction half equation"` `(i)`

`underbrace(N_3^(-) rarr 3/2N_2(g)+ e^(-) )_"oxidation half equation"` `(ii)`

And so we add `(i)` and `(ii)` in the usual way to eliminate the electrons....

`NaN_3(s) rarr 3/2N_2(g) + Na(s)`

And so we start with a solid reagent, the nitride salt, and electrical ignition gives rise to A GASEOUS PRODUCT...i.e. dinitrogen....and each `83*g` mass of sodium nitride gives rise to a volume of approx. `36*L` dinitrogen, that inflates the bag, and hopefully cushions your nut when it strikes the steering wheel...