10 g of acetic acid are combined with 5 g of sodium bicarbonate in a beaker with a mass of 25 g. After the reaction, the mass of the beaker with the new solution was only 39 g. How ould this change in mass be explained?
To explain the change in mass after the reaction, we need to understand the reaction that took place between acetic acid and sodium bicarbonate. The reaction between these two compounds produces carbon dioxide gas, water, and a salt called sodium acetate.
The balanced chemical equation for this reaction is as follows:
CH₃COOH (acetic acid) + NaHCO₃ (sodium bicarbonate) → CH₃COONa (sodium acetate) + CO₂ (carbon dioxide) + H₂O (water)
Given that we started with 10 g of acetic acid and 5 g of sodium bicarbonate, we can calculate the theoretical yield (the expected amount of products) using stoichiometry. From the balanced equation, we can see that the molar ratio between acetic acid and sodium bicarbonate is 1:1. Therefore, both substances will be completely consumed in the reaction, resulting in a total of 15 g of products (sodium acetate, carbon dioxide, and water).
However, after the reaction, the mass of the beaker with the new solution was only 39 g, which indicates that some mass was lost. This can be explained by the formation of carbon dioxide gas, which was released during the reaction. The gas escaped into the surroundings, resulting in a loss of mass from the system.
To calculate the mass lost due to the carbon dioxide gas, we can subtract the mass of the products formed (15 g) from the total mass lost (25 g - 39 g = -14 g). Therefore, the mass lost due to the carbon dioxide gas would be -14 g. This negative value indicates that the mass of carbon dioxide produced was higher than the mass of the products formed, which is not physically possible.
In summary, the change in mass after the reaction can be explained by the release of carbon dioxide gas, which escaped from the system, resulting in a loss of mass.