Question
Kevin's Experiment
Kevin's Experiment
Kevin sets up a simple science experiment. He fills a test tube with sodium hydroxide solution. Then, he ties a string around the test tube and pulls it tight under the stopper of a flask containing a copper sulfate solution. When Kevin releases the string, the test tube falls into the copper sulfate solution and the two solutions combine. A diagram of the setup is shown.
The setup on the left shows a flask partially filled with copper sulfate solution closed with a stopper. Inside the closed flask is a small test tube filled with sodium hydroxide solution attached to a string hovering above the copper sulfate solution. The flask sits on an electronic balance that shows the mass of the setup is 67.25 grams. An arrow pointing to the right shows the solutions mix thoroughly. The setup on the right shows the closed flask with sodium sulfate solution inside. The small test tube is in the solution and pieces of solid copper hydroxide have formed. The flask sits on an electronic balance that shows the mass of the new setup is unknown.
Constructed Response Question
Explain a reason Kevin used a stopper in his experimental setup AND what could happen to the mass of the products of this reaction if the stopper were not used.
Kevin's Experiment
Kevin sets up a simple science experiment. He fills a test tube with sodium hydroxide solution. Then, he ties a string around the test tube and pulls it tight under the stopper of a flask containing a copper sulfate solution. When Kevin releases the string, the test tube falls into the copper sulfate solution and the two solutions combine. A diagram of the setup is shown.
The setup on the left shows a flask partially filled with copper sulfate solution closed with a stopper. Inside the closed flask is a small test tube filled with sodium hydroxide solution attached to a string hovering above the copper sulfate solution. The flask sits on an electronic balance that shows the mass of the setup is 67.25 grams. An arrow pointing to the right shows the solutions mix thoroughly. The setup on the right shows the closed flask with sodium sulfate solution inside. The small test tube is in the solution and pieces of solid copper hydroxide have formed. The flask sits on an electronic balance that shows the mass of the new setup is unknown.
Constructed Response Question
Explain a reason Kevin used a stopper in his experimental setup AND what could happen to the mass of the products of this reaction if the stopper were not used.
Answers
GPT-4o mini
Kevin used a stopper in his experimental setup to ensure that the reaction occurring between the sodium hydroxide solution and copper sulfate solution happens in a closed system. This prevents the escape of gases or aerosols that may form during the reaction, thereby allowing for accurate measurement of mass and maintaining safety by containing any potentially harmful spills or splashes.
If the stopper were not used, the mass of the products of the reaction could potentially decrease. This is because gases that might be released during the reaction (such as water vapor if heat is generated or any other volatile compounds) would escape into the environment. Therefore, the observed mass of the products in an open system could be lower than the total mass of the initial reactants, leading to an inaccurate representation of the reaction's total mass. This emphasizes the importance of conducting reactions in a controlled and closed environment to preserve the integrity of the experimental data.
If the stopper were not used, the mass of the products of the reaction could potentially decrease. This is because gases that might be released during the reaction (such as water vapor if heat is generated or any other volatile compounds) would escape into the environment. Therefore, the observed mass of the products in an open system could be lower than the total mass of the initial reactants, leading to an inaccurate representation of the reaction's total mass. This emphasizes the importance of conducting reactions in a controlled and closed environment to preserve the integrity of the experimental data.