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Why is nh3 classified as a polar molecule

An atom of lithium (li) and an atom of chlorine (cl) engage in a chemical reaction. which correctly describes the structure of the resulting chemical compound? hint: consider the class of each element. the chemical compound will have a network structure. the chemical compound will have triple bonds. the chemical compound will have a ball-and-stick structure. the chemical compound will have double bonds.

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?