When perfectly pure phosphorus is a white, transparent, waxy solid, but as usually prepared it is yellowish owing to the presence of the allotropic " red phosphorus," J.
Several allotropic forms of phosphorus have been described, and in recent years much work has been done towards settling their identities.
Several allotropic forms of selenium have been described, but the work of A.
No Doubt There Must Be Approximate Relations Between The Atomic And Molecular Heats Of Similar Elements And Compounds, But Considering The Great Variations Of Specific Heat With Temperature And Physical State, In Alloys, Mixtures Or Solutions, And In Allotropic Or Other Modifications, It Would Be Idle To Expect That The Specific Heat Of A Compound Could Be Accurately Deduced By Any Simple Additive Process From That Of Its Constituents.
The monovalent iodine, for instance, is transformed by heating into an allotropic form, corresponding to the formula I, whereas ordinary iodine answers to I 2.