Question

Which of the following equations is balanced correctly? A. 3 H2O → H2 + 3 O2 B. Cl2 + 2 KBr → KCl + Br2 C. 2 C2H2 + 5 O2 → 4 CO2 + 2 H2O D. 2 C3H3 + O2 → 2 CO2 + H2O

Answer 1

A. the carbons are unbalanced B. the hydrogens are unbalanced. D. the chlorines are unbalanced. That leaves C. to be correctly balanced.

Answer 2

Answer:

The correct answer is option C.

Explanation:

In balanced chemical reaction, number of atoms of each elements are equal on both the sides of the chemical reaction.

A. $3H_2O\rightarrow  H_2 + 3O_2$

Number of hydrogen atoms on reactant side : 6

Number of oxygen atoms on reactant side : 3

Number of hydrogen atoms on product side : 2

Number of oxygen atoms on product side : 6

Reaction is balanced incorrectly.

B. $Cl_2 + 2KBr \rightarrow KCl + Br_2$

Number of chlorine atoms on reactant side : 2

Number of potassium atoms on reactant side : 2

Number of bromine atoms on reactant side : 2

Number of chlorine atoms on product side : 1

Number of potassium atoms on product side : 1

Number of bromine atoms on product side : 2

Reaction is balanced incorrectly.

C. $2 C_2H_2 + 5O_2 \rightarrow 4CO_2 + 2H_2O$

Number of hydrogen atoms on reactant side : 4

Number of oxygen atoms on reactant side : 10

Number of carbon atoms on reactant side : 4

Number of hydrogen atoms on product side : 4

Number of oxygen atoms on product side : 10

Number of carbon atoms on product side : 4

Reaction is balanced correctly.

D. $2 C_3H_3 +O_2 \rightarrow 2CO_2 + H_2O$

Number of hydrogen atoms on reactant side : 6

Number of oxygen atoms on reactant side : 2

Number of carbon atoms on reactant side : 6

Number of hydrogen atoms on product side : 2

Number of oxygen atoms on product side : 5

Number of carbon atoms on product side : 2

Reaction is balanced incorrectly.