Chemical Reactions and Mass Changes

Mr. B guides students through a virtual lab on the law of conservation of mass. The lab consists of three trials using different containers: a beaker, a bottle, and a flask with a balloon. Each trial involves measuring the mass of reactants and products to observe mass changes. The video concludes with a post-lab analysis discussing the results and potential errors, emphasizing the importance of a closed system to uphold the law of conservation of mass.

What was the initial mass of the empty beaker in Trial 1?

• 39.27 grams

• 45.48 grams

• 40.51 grams

• 25.94 grams

In Trial 1, what was the total mass of the beaker and vinegar before adding baking soda?

• 40.51 grams

• 39.27 grams

• 25.94 grams

• 45.48 grams

What was the final mass of the products in Trial 1 after the reaction?

• 25.94 grams

• 39.27 grams

• 40.51 grams

• 45.48 grams

During Trial 2, what was the mass of the empty bottle?

• 45.12 grams

• 59.82 grams

• 64.88 grams

• 63.62 grams

What was the total mass of the reactants in Trial 2 before the reaction?

• 63.62 grams

• 59.82 grams

• 45.12 grams

• 64.88 grams

In Trial 3, what was the mass of the empty flask?

• 143.76 grams

• 144.80 grams

• 136.94 grams

• 122.31 grams

What was the total mass of the reactants in Trial 3 before the reaction?

• 122.31 grams

• 136.94 grams

• 144.80 grams

• 143.76 grams

What evidence indicated a chemical reaction occurred during the lab?

• Change in color

• Solidification

• Temperature decrease

• Formation of a gas

How did the final mass of the products compare to the initial mass of the reactants in Trial 1?

• Slight decrease

• Significant decrease

• Slight increase

• No change

What was a major reason for the mass change observed in the trials?

• Incorrect measurements

• Gas escape

• Equipment malfunction

• Temperature fluctuations