Answer:

Explanation:
It often helps to write the heat as if it were a reactant or a product in the thermochemical equation.
Then you can consider it to be 11018 "moles" of "kJ"
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
M_r: 32.00
2C₈H₁₈ + 25O₂ ⟶ 16CO₂ + 8H₂O + 11 018 kJ
n/mol: 7280
1. Moles of O₂
The molar ratio is 25 mol O₂:11 018 kJ

2. Mass of O₂

Answer:
In this conditions, the gaswll weight 46.74 g.
Explanation:
The idal gas law states that:
PV = nRT,
P: pressure = 740 mmHg = 0.97 atm
V: volume = 14.5 L
n: number of moles
R: gas constant =0.08205 L.atm/mol.K
T: temperature = 29°C = 302.15K

1 mol gas ___ 82 g
0.57 mol gas __ x
x = 46.74 g