Rob and his sister joan are standing on their apartment balcony. rob throws a ball straight out from the balcony. at the same time, joan drops a ball straight down. both balls reach the ground at the same time. which factor causes the two balls to reach the ground at the same time?

If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin?

Adilute aqueous potassium nitrate solution is

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 .