Question

Which is the balanced chemical equation representing the reaction between

Answer 1

Answer:

Choice A: $\rm 1\; C_2H_4 O_2 + 1\;NaHCO_3 \to 1\;NaC_2H_3O_2 + 1\;H_2O + 1\;CO_2$.

Explanation:

Indeed it is possible to balance this equation by the conservation of atoms in a chemical reaction. However, knowing what's actually going on in this process will likely make this problem easier to solve.

Vinegar contains acetic acid $\rm C_2H_4 O_2$. Acetic acid is a monoprotic acid. In other words, each $\rm C_2H_4 O_2$ can dissociate to produce up to one hydrogen ion $\rm H^{+}$. That is:

$\rm C_2H_4 O_2 \rightleftharpoons {C_2H_3 O_2}^{-} + H^{+}$.

Baking soda is a common name for sodium bicarbonate $\rm NaHCO_3$. Each formula unit of $\rm NaHCO_3$ contains one bicarbonate ion: $\rm {HCO_3}^{-}$. Each bicarbonate ion will consume one hydrogen ion to produce water and carbon dioxide:

$\rm {HCO_3}^{-} + H^{+} \to H_2O + CO_2$.

For this chemical equation to balance, the number of hydrogen ions that $\rm C_2H_4 O_2$ supplies shall be the same as the number of these ions that $\rm NaHCO_3$ consumes. Each unit of $\rm C_2H_4 O_2$ supplies one unit of hydrogen ions while each unit of $\rm NaHCO_3$ consumes one unit of hydrogen ions. Reacting the two at a one-to-one ratio will make sure that this reaction neither run short of hydrogen ions or produce more hydrogen ions than it need.

Hence the coefficient in front of $\rm C_2H_4 O_2$ and $\rm NaHCO_3$ shall be the same. Let their coefficients be one.

$\rm 1\; C_2H_4 O_2 + 1\;NaHCO_3 \to ?\;NaC_2H_3O_2 + ?\;H_2O + ?\;CO_2$.

Now, balance this equation with reference to the number of atoms:

• One Na atom;
• Five H atoms;
• Five O atoms;
• Three C atoms.

$\rm 1\; C_2H_4 O_2 + 1\;NaHCO_3 \to 1\;NaC_2H_3O_2 + 1\;H_2O + 1\;CO_2$.

Answer 2

Answer:

The correct option is OA.

C2H4O2 + NaHCO3 - NaC2H302 + H2O + CO2

Explanation:

To solve this you have to check the number of elements in both sides of the equation.