Sodium metal reacts is with water to form sodium hydroxide and hydrogen gas. why is this a chemical change?

Which are forms of frozen water? check all that apply. dew frost hail rain sleet

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. in the first step, calcium carbide and water react to form acetylene and calcium hydroxide: cac2 (s) + 2h2o (g) → c2h2 (g) + caoh2 (s) =δh−414.kj in the second step, acetylene, carbon dioxide and water react to form acrylic acid: 6c2h2 (g) + 3co2 (g) + 4h2o (g) → 5ch2chco2h (g) =δh132.kj calculate the net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water and carbon dioxide from these reactions. round your answer to the nearest kj .

Which words or phrases identify layers of groundwater? check all that apply. water table kettle lake saturation zone underground lake sinkhole will give brainiest, answer quickly.