please if anyone can help

Question

Select the missing reactant for the following combustion reaction

2 _______________ + 15 O2 ---> 14 CO2 + 6 H2O

Group of answer choices

Answer 1

Looking at the products, we can see there are a total of 14 C atoms, 34 O atoms, and 12 H atoms.

In the reactants we see that 30 O atoms are in the form of O₂ leaving us with 14 C atoms, 4 O atoms, and 12 H atoms to work with.

There are two of the missing reactant molecules, so we can divide the remaining atom values by 2 to figure out what the missing molecule is. If we do this, we find that the missing reactant is C₇O₂H₇.