The temperature of a typical laboratory freezer unit is -20°C. If liquid water in a completely filled, closed container is placed in the freezer, estimate the maximum pressure developed in the container at equilibrium. The enthalpy of fusion of water may be taken as 333.4 kJ kg-1 , independent of temperature and pressure, and the densities of ice and liquid water at -20°C are 0.9172 and 1.00 g cm-3 , respectively.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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