Question

model 2 - results of alka - seltzer® experiment
trial number of alka - seltzer tablets volume of vinegar (ml) room pressure (kpa) initial temp (°c) (vinegar solution) final temp. (°c) (final mixture)
trial 1 1 100.0 84 23.5 22.6
trial 2 2 100.0 84 23.5 21.5
trial 3 3 100.0 84 23.5 20.4
trial 4 4 100.0 84 23.5 19.2
trial 5 5 100.0 84 23.5 18.1

1. which trial in the model 2 data table corresponds to the reaction illustrated in model 1?
2. consider the five trials that produced the data in model 2.

a. what variable was purposefully changed in the experiment?
b. what variable changed as a result of changing the variable listed in part a?

1. what variable(s) shown in the model 2 data table remained constant among all the trials?

Explanation:

Step1: Analyze the experiment variables

In the experiment, we need to identify independent, dependent and controlled variables.

Step2: Identify the independent variable

The number of Alka - Seltzer tablets was purposefully changed. It is the independent variable.

Step3: Identify the dependent variable

The final temperature of the final mixture changed as a result of changing the number of tablets. It is the dependent variable.

Step4: Identify the constant variables

The volume of vinegar (100.0 mL), room pressure (84 kPa) and initial temperature of vinegar solution (23.5 °C) remained constant among all trials.

Answer:

6a. The number of Alka - Seltzer tablets.
6b. The final temperature of the final mixture.

1. Volume of vinegar (100.0 mL), room pressure (84 kPa), initial temperature of vinegar solution (23.5 °C).