The use of zinc Because zinc is easy to form a protective film on its surface at room temperature, the biggest use of zinc is in the zinc plating industry. Zinc can form alloys with many non-ferrous metals, among which alloys of zinc with aluminum and copper are widely used in die casting. Brass consisting of zinc, copper, tin and lead, used in machinery manufacturing. Zinc plate containing a small amount of lead, cadmium and other elements can be made into negative electrode of zinc-manganese dry battery, printed zinc plate, powder etching photographic plate and offset printing plate. Zinc can react with acid or strong alkali to release hydrogen. Zinc fertilizer (zinc sulfate, zinc chloride) can promote plant cell respiration and carbohydrate metabolism. Zinc powder, lithopone and zinc chrome yellow can all be used as pigments. Zinc oxide can also be used in medicine, rubber, coatings and other industries. In nature, zinc mostly exists in sulfide state. The main zinc-bearing mineral is sphalerite. There are also a few oxidized minerals, such as smithsonite and wurtzite. /question/39811813.html germanium is widely used. It is widely used in electronic industry, alloy pretreatment, optical industry, medical care and other fields, and can also be used as a catalyst. High purity germanium is an excellent semiconductor material. Germanium single crystal doped with a small amount of specific impurities can be used to manufacture various transistors, rectifiers and other devices. As a thermoelectric battery material, it can be used to manufacture solar cells, photovoltaic cells, thermistors, thin film resistors, semiconductor thermometers, germanium windows, prisms or lenses specially transmitting infrared rays. Germanium compounds are used to make fluorescent plates and various high refractive index glasses. With the rapid development of infrared technology, metal germanium is more and more widely used in the optical system of infrared instruments such as thermal imaging, imaging tracking, infrared forward-looking and infrared night vision. Due to the improvement of coating technology, the transmittance of optical germanium is close to that of optical glass. At the same time, solar cells and PET catalysts have opened up more space for the application of germanium.