<span>The smallest unit of a compound is called a molecule. The correct option among all the options that are given in the question is the second option or the penultimate option or option "B". The other choices are incorrrect and can be negated. I hope that this is the answer that has actually come to your desired help.</span>
Molar mass O2 = 31.99 g/mol
Molar mass CO2 = 44.01 g/mol
Moles ratio:
<span>C3H8 + 5 O2 = 3 CO2 + 4 H2O
</span>
5 x 44.01 g O2 ---------------- 3 x 44.01 g CO2
( mass of O2) ------------------ 37.15 g CO2
mass of O2 = 37.15 x 5 x 44.01/ 3 x 44.01
mass of O2 = 8174.8575 / 132.03
mass of O2 = 61.916 g
Therefore:
1 mole O2 ----------------- 31.99 g
moles O2 -------------------- 61.916
moles O2 = 61.916 x 1 / 31.99
moles = 61.916 / 31.99 => 1.935 moles of O2
Well, first we must remember that

This is because


So then

The rate of chemical reactions generally happen <em>faster</em> when the temperature is raised.
This happens because the reactant's molecules move faster when the temperature is raised. The molecules start to bounce around more, increasing the chance for the reaction to happen, or to increase the speed at which the reaction occurs. Hope this helped.