Which is a physical change of iodine?

Scientists have developed an explanation of a phenomenon from several verified hypotheses. the explanation has been confirmed through numerous experimental tests. which option best describes this explanation? a. scientific lawb. research questionc. hypothesisd. scientific theory

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 .

If you need to add 27.50ml of a solution, which piece of glassware would you use to deliver this volume and explain how you would determine if the 27.50 ml was measured?