Which of the following equations demonstrates the law of conservation of mass

Question

A. Ch4 +O2 ->C+2H20
B. CH+02->CO2+H2O
C. CH4+02->CO2+HO
D. CH4+O2->CO2+H2O

Answer 1

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction. This means that the number of atoms of each element must be the same on both sides of the equation.

Let's examine each option:

A. \( CH_4 + O_2 \rightarrow C + 2H_2O \)

• Left: 1 C, 4 H, 2 O
• Right: 1 C, 4 H, 2 O
• Conservation of mass is satisfied.

B. \( CH + O_2 \rightarrow CO_2 + H_2O \)

• Left: 1 C, 1 H, 2 O
• Right: 1 C, 2 H, 3 O
• Conservation of mass is not satisfied.

C. \( CH_4 + O_2 \rightarrow CO_2 + HO \)

• Left: 1 C, 4 H, 2 O
• Right: 1 C, 4 H, 3 O
• Conservation of mass is not satisfied. (There should be \( H_2O \) instead of \( HO \))

D. \( CH_4 + O_2 \rightarrow CO_2 + H_2O \)

• Left: 1 C, 4 H, 2 O
• Right: 1 C, 2 H, 3 O
• Conservation of mass is not satisfied. (This should balance as \( CH_4 + 2O_2 \) to have 4 H on both sides)

Among these options, A is the only equation that correctly demonstrates the law of conservation of mass.