Question

When the equation, ___O2 + ___C 6H 14 →→ ___CO2 + ___H2O is balanced, the coefficient of O2 is:

Answer 1

Explanations:

For a chemical reaction to be balanced, the total number of moles of elements at the reactant must be equal to the number of moles at the product.

Given the chemical reaction;

`aO_2+bC_6H_(14)\rightarrow cCO_2+dH_2O`

Equating the number of moles of elements on both sides:

For the oxygen element:

2a = 2c + d ................... 1

For the carbon element;

6b=c

For the Hydrogen element:

14b = 2d

7b = d .............................. 3

Assume a = 2;

Equation 1 becomes:

2(2) = 2c + d

4 = 2c + d ................,....4

From equation 2

b = c/6 .............................. 5

From equation 3:

b = d/7 ...................... 6

Equating 5 and 6

c/6 = d/7

7c = 6d

c = 6d/7 ........................... 7

Substitute equation 7 into 4 to have:

4 = 2c + d

4 = 2(6d/7) + d

4 = 12d/7 + d

4 = (12d+7d)/7

28 = 19d

d = 28/19

To get the value of b:

b = d/7

b = 28/19 * 1/7

b = 28/133