what is the oxidation state of ge in geh4
Germanium Elemental germanium oxidizes slowly to GeO2 at 250 °C.[32] Germanium is insoluble in dilute acids and alkalis but dissolves slowly in hot concentrated sulfuric and nitric acids and reacts violently with molten alkalis to produce germanates ([GeO3]2−). Germanium occurs mostly in the oxidation state +4 although many +2 compounds are known.[33] Other oxidation states are rare: +3 is found in compounds such as Ge2Cl6, and +3 and +1 are found on the surface of oxides,[34] or negative oxidation states in germanes, such as −4 in GeH4. Germanium cluster anions (Zintl ions) such as Ge42−, Ge94−, Ge92−, [(Ge9)2]6− have been prepared by the extraction from alloys containing alkali metals and germanium in liquid ammonia in the presence of ethylenediamine or a cryptand.[33][35] The oxidation states of the element in these ions are not integers—similar to the ozonides O3−.
Hofmann voltameter A Hofmann voltameter is an apparatus for electrolysing water, invented by August Wilhelm von Hofmann (1818â€“1892)[1] in 1866. It consists of three joined upright cylinders, usually glass. The inner cylinder is open at the top to allow addition of water and an ionic compound to improve conductivity, such as a small amount of sulphuric acid. A platinum electrode is placed inside the bottom of each of the two side cylinders, connected to the positive and negative terminals of a source of electricity. When current is run through Hofmann's voltameter, gaseous oxygen forms at the anode and gaseous hydrogen at the cathode. Each gas displaces water and collects at the top of the two outer tubes.