Strontium is a silvery-white crystalline metal of about the same hardness as lead. The density, according to Guntz and Galliot, is 2.63. All the values given by other investigators are somewhat lower, but that is probably due to the presence of impurities. The specific heat is 0.0742. The melting-point is about 800° C., and the metal volatilises at a slightly higher temperature. The specific electrical resistance is 2.48×10-5 ohm per c.c. Metallic strontium is photoelectrically sensitive, the maximum effect being obtained under green light. The ionic mobility of ½Sr• is 51.
The most intense lines in the spectrum of strontium measured in Angstrom units are the following: -
Arc: Ultra-violet: 2932.0, 3307.6, 3351.3, 3464.6; Visible: 4077.9, 4215.7, 4305.6, 4607.5, 4812.0, 4832.2, 4872.7, 4968.1, 5229.5, 5451.1, 5970.4, 6380.9, 6388.5, 6550.5; Infra-red: 10038.3, 10916.3, 20262.4.
Spark: Ultra-violet: 2322.4, 3380.9, 3464.6, 3475.0; Visible: 3705.9, 4030.5, 4077.9, 4162.0, 4215.7, 4305.6, 4607.5, 6504.3, 6892.9. |