Question

tablet 25
water 10
baggie 4
total 39\ttotal 38
matt and juan are studying chemical reactions and the law of conservation of matter in science. each lab group conducted an experiment to verify the law. the boys’ materials can be seen in the data table: antacid tablet, water, and a zip lock baggie. they found the mass of all the materials and recorded the mass in grams in the table as well, then calculated the total mass of the system. matt placed the tablet in the baggie and then juan poured in the water. the boys closed the baggie (waited until the tablet disappeared). when the reaction was completed, they found the mass of the system again. note their results in the data table. elaborate on the most logical reason why the data did not support the law of conservation of matter.
a the boys did not know how to use the balance properly.
b the reaction produced gas bubbles and they have no mass.
c some of the water evaporated and could not be massed as a product in the reaction
d some gas escaped from the baggie before the boys had it completely closed.

Explanation:

• Option A: Assuming they didn't use the balance properly is not the most logical reason as the initial total was calculated, and the issue is likely related to the reaction and system closure.
• Option B: Gases do have mass, so this statement is incorrect.
• Option C: The reaction involves an antacid tablet (likely a carbonate reacting with water/acid) producing gas, not just water evaporation. Evaporation of water would have a minimal effect compared to gas escape.
• Option D: When the antacid tablet reacts with water, gas (like CO₂) is produced. If the baggie wasn't closed completely before the reaction finished, some gas escaped, leading to a lower final mass, which explains why the data didn't support the law of conservation of matter (which states mass is conserved in a closed system).

Answer:

D. Some gas escaped from the baggie before the boys had it completely closed