Dynamic viscosity of liquid gallium at different temperatures Junjie Chen Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China Contributor: Junjie Chen, ORCID: 0000-0001-5055-4309, E-mail address: komcjj@gmail.com Gallium is a chemical element, metal of main Group 13 of the periodic table. It liquefies just above room temperature. Gallium does not occur free or concentrated in independent minerals. It is extracted as a by-product from zinc blende, iron pyrites, bauxite, and germanite. Gallium is silvery white and soft enough to be cut with a knife. It takes on a bluish tinge because of superficial oxidation. Unusual for its low melting point, gallium also expands upon solidification and supercools readily, remaining a liquid at temperatures as low as 0 degrees Celsius. Gallium remains in the liquid phase over a temperature range of about 2,000 degrees Celsius, with a very low vapour pressure up to about 1,500 degrees Celsius, the longest useful liquid range of any element. The liquid metal clings to glass and similar surfaces. The crystal structure of gallium is orthorhombic. Natural gallium consists of a mixture of two stable isotopes: gallium-69 and gallium-71. Gallium has been considered as a possible heat-exchange medium in nuclear reactors, although it has a high neutron-capture cross section. The metal gallium is stable in dry air. Somewhat similar to aluminum chemically, gallium slowly oxidizes in moist air until a protective film forms. On burning in air or oxygen, it forms the white oxide. This oxide can be reduced to the metal when heated at high temperatures in hydrogen. Gallium is amphoteric, reacting with sodium and potassium hydroxide solutions to yield a gallate and hydrogen gas. The halogens attack it vigorously. Temperature (degrees Celsius), Dynamic viscosity (grams per meter per second) 350 1.369 400 1.158 450 1.016 500 0.915 550 0.840 600 0.783 650 0.737 700 0.700 750 0.669 800 0.643 Contributor: Junjie Chen, ORCID: 0000-0001-5055-4309, E-mail address: komcjj@gmail.com, Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China

Contributor: Junjie Chen, ORCID: 0000-0001-5055-4309, E-mail address: komcjj@gmail.com, Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China