A student combines two liquids in a beaker. She observes that the mass of the combined liquid is less than the mass of the two separate liquids. The students claims that this observation shows that matter is not conserved in chemical reactions. Which statement explains why the students claim is incorrect?
1. The product contained fewer atoms than the reactants.
2. The reaction produced a gas that escaped the beaker.
3. The combined liquid was warmer than the two separate liquids.
4. The reaction did not change the physical properties of the liquid.
Option 2. The reaction produced a gas that escaped the beaker.
The correct statement that explains why the students claim is incorrect is:
2. The reaction produced a gas that escaped the beaker.
This is because when a gas is produced during a chemical reaction and it escapes the container, it can result in a loss of mass. This loss of mass does not mean that matter is not conserved, but rather that the mass has been distributed differently due to the escape of the gas.
The correct statement that explains why the student's claim is incorrect is 2. The reaction produced a gas that escaped the beaker.
To understand why this is the correct statement, let's consider the law of conservation of mass. According to this law, mass is conserved in chemical reactions, which means that the total mass of the reactants must be equal to the total mass of the products.
In this case, the student observes that the mass of the combined liquid is less than the mass of the two separate liquids. However, this does not mean that matter is not conserved. It simply suggests that something else is happening.
Option 1 states that the product contained fewer atoms than the reactants. While this could be a possibility, it is not the main reason for the decrease in mass in this particular scenario.
Option 3 states that the combined liquid was warmer than the two separate liquids. While temperature changes can affect the density of liquids, it does not explain why the mass is reduced.
Option 4 states that the reaction did not change the physical properties of the liquid. However, this does not provide an explanation for the decrease in mass.
Option 2, on the other hand, states that the reaction produced a gas that escaped the beaker. This explanation accounts for the decrease in mass. If a gas is produced during the reaction and it escapes the beaker, then the total mass of the combined liquid will be less than the sum of the masses of the two separate liquids.
Therefore, option 2 is the correct statement that explains why the student's claim is incorrect.