an experiment, a 0.280-kg piece of ceramic superconducting material at 23 °C is placed in liquid nitrogen at its boiling point (−195.8 °C) to cool. The nitrogen is in a perfectly insulated flask that allows the gaseous N2 to escape immediately. How much mass of liquid nitrogen will be boiled away? (Take the specific heat of the ceramic material to be the same as that of glass.)

Answer 1

This is worked almost the same as the Al/Cu problem above.
heat lost by ceramic on cooling is
q = mass ceramic x specific heat ceramic x (Tfinal-Tinitial)
Then look up heat vaporization liquid nitrogen.
joules lost by ceramic = mass N2 x heat vaporization liquid N2. Solve for mass N2.