To obtain the metal chemically pure a specially prepared pure oxide or salt of zinc is distilled.
Metals may unite chemically both with metals and with non-metals.
Chemically related to vanadium are the two elements tantalum and columbium or niobium.
Lord Rayleigh in 1894 found that the density of atmospheric nitrogen was about 2% higher than that of chemically prepared nitrogen, a discovery which led to the isolation of the rare gases of the atmosphere.
Specimens of the best known and of many of the lesser known rubbers are included in the Colonial and Indian Collections and Sample Rooms of the Imperial Institute, and many of the authentic specimens have been chemically and technically examined in the Scientific and Technical Department of the Institute and commercially valued.