Physical Properties of Molybdenum

In the massive metallic condition, pure molybdenum is a white malleable substance, not sufficiently hard to scratch glass, and of density, at 26° C., 10.281.4 At 20° C. its compressibility is 0.47×10^-6 per megabar. The following values have been obtained for the specific heat of molybdenum:

Temperature, ° C.	Specific Heat.
20 to 550	0.07219
20 to 100	0.06468
-188 to +20	0.0555
-253 to -196	0.0141

The mean coefficient of expansion of molybdenum for the temperature range 25° C. to 100° C. is 4.9×10^-6, while for the range 25° C. to 500° C. the mean coefficient is 5.5×10^-6.

Molybdenum is paramagnetic. Numerous determinations of the magnetic susceptibility have been made, but the results obtained are widely divergent. When obtained in the form of a powder it is grey in colour and lustreless, though the strongly compressed powder exhibits metallic lustre. The metal melts at 2450 ± 30° C., and may, though with difficulty, be distilled in the electric furnace.

The emission of electrons from molybdenum has been observed.