Item SC092004: When a liquid changes to a gas in a sealed container and the number of atoms stays the same, the mass of the jar and everything in it also stays the same.

A student placed a liquid in a jar and sealed it.  Then she heated the liquid and it turned into a gas.  If the number of atoms in the sealed jar stayed the same, what happened to the mass of the jar and everything inside it after she heated it?

  1. The mass increased.
  2. The mass decreased.
  3. The mass stayed the same.
  4. It depends on whether a chemical reaction occurred.

Distribution of Responses

Chart showing distrubtion of responses for Item SC092004

Percent of students responding correctly

Grades 6–834%
Grades 9–1243%
Primary Language is English38%
Primary Language is not English29%

View data table