The scientist used the law of conservation of mass, which states that in a chemical reaction, the total mass of the reactants must equal the total mass of the products. Since all the reactants are converted into products, the combined mass of 12.7 grams of copper and 3.2 grams of sulfur equals 15.9 grams of copper sulfide.
Use the chemical equation to complete the activity. 2Cu+S→Cu2S Copper (Cu) reacts with sulfur (S) to form copper sulfide as shown in the equation. A scientist adds 12.7 grams of Cu to 3.2 grams of S to start the reaction. In this reaction, all of the copper and all of the sulfur react. Before running the experiment, the scientist expected the products of the reaction will be a total of 15.9 grams of copper sulfide (Cu2S). In 1–2 sentences, explain the law that the scientist used to predict that the product of the reaction would be 15.9 grams of copper sulfide. (2 points).
3 answers
can you make it sound like a 7th grader
The scientist used the law of conservation of mass, which says that matter can't be created or destroyed in a chemical reaction. This means that the total weight of the copper and sulfur before the reaction must be the same as the weight of the copper sulfide produced after the reaction, which is why they expected it to be 15.9 grams.