Questions 10-13 refer to the following information. Cu(s) + 4 HNO3(aq) → Cu(NO3)2(aq) + 2 NO2(g) + 2 — Kinetics Chemistry Question
Question
Questions 10-13 refer to the following information.
Cu(s) + 4 HNO3(aq) → Cu(NO3)2(aq) + 2 NO2(g) + 2 H2O(l)
Each student in a class placed a 2.00 g sample of a mixture of Cu and Al in a beaker and placed the beaker in a fume hood. The students slowly poured 15.0 mL of 15.8 M HNO3(aq) into their beakers. The reaction between the copper in the mixture and the HNO3(aq) is represented by the equation above. The students observed that a brown gas was released from the beakers and that the solutions turned blue, indicating the formation of Cu2+(aq). The solutions were then diluted with distilled water to known volumes.
- In one student's experiment the reaction proceeded at a much slower rate than it did in the other students' experiments. Which of the following could explain the slower reaction rate?
In the student's sample the metal pieces were much smaller than those in the other students' samples.
The student heated the reaction mixture as the HNO3(aq) was added.
The student used a 1.5 M solution of HNO3(aq) instead of a 15.8 M solution of HNO3(aq).
The student used a 3.00 g sample of the mixture instead of the 2.00 g sample that was used by the other students.