Gallium

Gallium can be used to made of optical glass, vacuum tube, semiconductor materials; into the quartz thermometer can be high temperature measurement; joining of aluminum can be prepared easily heat treated alloy; gallium and gold alloy used in decoration and prosthodontic; also used to as catalysts for organic synthesis.

Gallium is silver white metal. Density 5.904 g / cm 3. Melting point 29.78. Boiling point 2403. Valence 2 and 3. The first ionization energy of 5.999 electron volts. Freezing point is very low. Because of the complex structure of the stable solid, the pure liquid has the obvious tendency to be too cold, so it can be put in the ice bath for several days without crystallization. Soft, brittle, stable in the air. Heat soluble in acid and alkali; react violently with boiling water, but only slightly react with water at room temperature. High temperature can be the role of most of the metal. When the liquid is converted to solid, the expansion rate is 3.1%, which is suitable to be stored in plastic containers. Chinese characters of gallium refers to a trivalent metallic element of the rare blue and white.

Gao Chunjia: purity gallium high, the general content of impurities in the total content of 10-5 in the following high purity gallium gallium. According to the content of gallium is divided into 5N, 6N, 7N and 8N a total of four levels. Soft, pale blue. Melting point 29.78. Boiling point 2403. Orthorhombic crystal, significant anisotropy. 0 the resistivity along the A, B, C, 10-6 three axes are 1.75 x m, 10-6, 8.20 * m, and 55.30 * m, 10-6. Ultra pure gallium residual resistivity ratio p 300K/ P 4.2K 55000. Chemical treatment, electrolytic refining, vacuum distillation, zone melting, drawing of single crystal and other methods to prepare. Mainly used in the field of electronic industry and communication, is the preparation of a variety of gallium compound semiconductor material, silicon, germanium semiconductor doping agent, nuclear reactor heat exchange medium.

In the process of establishing a periodic system of chemical elements, the elements of a similar nature become a family that has been accepted by the chemists. At that time, the French chemist Brouard Bond Ron using spectral analysis found that in the aluminum group, the lack of an element between aluminum and indium. From the beginning of 1865, he was looking for the elements with a spectroscope, analyzed many minerals, but without success. Until September 1875, he Bangdelang performed a set of experiments in the presence of French chemists, that new elements exist. 4.7 the proportion of new elements that determination of the Bois Bangdelang and Mendeleev periodic system of elements according to the calculated proportion of should is 5.9 ~ 6. Brouard Bond Ron again by the new element, confirmed the proportion should be 5.96. He named the substance gallium and the element symbol as Ga