Question

Propane reacts with elemental oxygen gas according to the unbalanced reaction, C3H8(g) + O2(g) → CO2(g) + H2O(l). What is the coefficient of the water, H2O(l), in the balanced reaction?

a
2
b
4
c
6
d
8

Answer 1

b. 4

Step-by-step explanation:

The reaction expression is given as:

C₃H₈ + O₂ → CO₂ + H₂O

To solve this problem, we employ a mathematical approach.

Now use coefficient a, b, c and d as the numbers that will balance the expression:

aC₃H₈ + bO₂ → cCO₂ + dH₂O

Conserving C: 3a = c

H: 8a = 2d

O: 2b = 2c + d

let a = 1, c = 3, d = 4 , b = 5

The balanced reaction expression is:

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O