At constant pressure, when the temperature of a gas is decreased, what happens to its volume?

Match the mixture with the substance// i really need on this guys (it’s a pic btw)

Name the element in group 17, period 2. (periodic table)

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.