Chapter 1.1, Problem 3R

To determine

To define: the dependent variable in an experiment that shows how the volume of gas changes with change in temperature.

Explanation of Solution

Introduction:

In an experiment, there are normally two main variables, independent and dependent variable. An independent variable is the variable that does not depend on anything and can be changed or adjusted. On the other hand, a dependent variable is the variable which changes automatically on adjustment of the independent variable. The value of dependent variable depends on the value of the independent variable. Change in the volume of gas is the dependent variable in an experiment showing how the volume of gas changes with changes in temperature.

Charles’ law of gas is used to explain the relation between temperature and volume of a gas. Charles’ temperature-volume law states that, the volume of a given amount of gas at constant pressure is directly proportional to the Kelvin temperature and is given as,

  $V\propto T$....................(1)

Here, V is the volume and T is the temperature measured in Kelvin.

Equation (1) can be written as,

  $V=kT$ ....................(2)

Here, k is the constant of proportionality.

From equation (2) it can be observed that, as the temperature changes the volume of the gas changes. Thus, this law describes that as the temperature increases the gas expands and its volume increases. Conversely, a decrease in temperature will result in decrease in volume of the gas. It can also be found that in this experiment, the change in volume of the gas is the dependent variable and the temperature is the independent variable.

Conclusion:

Hence, change in the volume of gas is the dependent variable in an experiment showing how the volume of gas changes with changes in temperature.