Item EG052004: For two balloons that contain the same number of helium atoms, the helium atoms in the balloon with the greater thermal energy are moving at the greater average speed.

A student has two balloons filled with helium gas, Balloon 1 and Balloon 2. The balloons have the same number of helium atoms in them.

If the thermal energy of the helium in Balloon 1 is increased so that the helium in Balloon 1 has more thermal energy than the helium in Balloon 2, which helium atoms would be moving faster on average?

  1. The helium atoms in Balloon 1 would be moving faster on average.
  2. The helium atoms in Balloon 2 would be moving faster on average.
  3. The helium atoms in Balloon 1 would be moving at the same average speed as the helium atoms in Balloon 2.
  4. The only way to tell which helium atoms would be moving faster on average is to also know the temperature of the helium in each balloon.

Distribution of Responses

Chart showing distrubtion of responses for Item EG052004

Percent of students responding correctly

Overall49%
Grades 6–846%
Grades 9–1252%
Male50%
Female48%
Primary Language is English50%
Primary Language is not English40%

View data table