Which gas law is applied in a fusible-plug pressure-relief valve?

a. Boyle's c. Dalton's
b. Charles' d. Gay-Lussac's

ANS: D
The pressure-release valve allows some of the gas on top of the liquid to escape if the contents are warmed too much. This release of gas allows the gas within the container to expand, thus lowering the temperature. This maintains the gas under pressure between its boiling point and its critical temperature so that the majority of the reservoir's contents will be maintained in the liquid state.