Balancing equations Knowledge-Based Download PDF

Questions

1. 1.

   Which of the following chemical equations is correctly balanced?

   • A) $\text{C}_2\text{H}_6 + 3\text{O}_2 \rightarrow 2\text{CO}_2 + 3\text{H}_2\text{O}$
   • B) $\text{Al} + 3\text{HCl} \rightarrow \text{AlCl}_3 + \text{H}_2$
   • C) $\text{Fe}_2\text{O}_3 + 2\text{CO} \rightarrow 2\text{Fe} + 2\text{CO}_2$
   • D) $2\text{KClO}_3 \rightarrow 2\text{KCl} + 3\text{O}_2$
2. 2.

   When the chemical equation $\text{C}_4\text{H}_{10} + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$ is balanced using the lowest whole-number coefficients, what is the ratio of the coefficient of $\text{O}_2$ to the coefficient of $\text{C}_4\text{H}_{10}$?

   • A) 13 : 2
   • B) 13 : 1
   • C) 9 : 2
   • D) 5 : 1
3. 3.

   Which set of stoichiometric coefficients $a, b, c, d$ balances the equation $a\text{FeS}_2 + b\text{O}_2 \rightarrow c\text{Fe}_2\text{O}_3 + d\text{SO}_2$ using the lowest whole-number integers?

   • A) 4, 11, 2, 8
   • B) 2, 5, 1, 4
   • C) 4, 10, 2, 8
   • D) 2, 11, 1, 4
4. 4.

   When the chemical equation $\text{NH}_3 + \text{O}_2 \rightarrow \text{NO} + \text{H}_2\text{O}$ is balanced using the lowest whole-number coefficients, what is the stoichiometric coefficient of $\text{O}_2$?

   • A) 3
   • B) 5
   • C) 6
   • D) 10
5. 5.

   When the chemical equation $\text{Al} + \text{H}_2\text{SO}_4 \rightarrow \text{Al}_2(\text{SO}_4)_3 + \text{H}_2$ is balanced using the smallest whole-number coefficients, what is the sum of all the stoichiometric coefficients?

   • A) 8
   • B) 9
   • C) 10
   • D) 12