Question

In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g of water, and 8.2 g of sodium ethanoate. Show that these observations are in agreement with the law of conservation of mass.

sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water.

Answer 1

• In the given reaction, sodium carbonate reacts with ethanoic acid to produce sodium ethanoate, carbon dioxide, and water.

Chemical equation:

$$\begin{gathered} {\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{s}\right)+{\mathrm{CH}}_3\mathrm{COOH}\left(\mathrm{l}\right)\to {\mathrm{CH}}_3\mathrm{COONa}\left(\mathrm{l}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Sodium}\mathrm{Ethanoic}\mathrm{acid}\mathrm{Sodium}\mathrm{Carbon}\mathrm{Water} \\ \mathrm{carbonate}\mathrm{ethanoate}\mathrm{dioxide} \end{gathered}$$

We need to show that the law of conservation of mass is agreed upon in the above reaction.

Law of conservation of mass:

• According to this law, mass can neither be created nor be destroyed but can be transformed from one form to another.
• This law also states that in a chemical reaction the mass of the reactant must be equal to the mass of the product.

Let us start from the reactant side:

• On the reactant side, we have sodium carbonate and ethanoic acid
• Mass of sodium carbonate=5.3g (given)
• Mass of ethanoic acid=6g (given)
• Now total mass before reaction that is mass of reactants = (5.3g + 6g) = 11.3g

Now let us check the product side:

• Mass of carbon dioxide = 2.2g (given)
• Mass of water = 0.9g (given)
• Mass of sodium ethanoate = 8.2g (given)

Now total mass after reaction that is mass of products = (8.2g + 2.2g + 0.9g) = 11.3g

According to the law of conservation of mass:
Total mass before reaction=total mass after reaction

Therefore, the given observation is in agreement with the law of conservation of mass.