1. Sodium hydroxide sold commercially has a soluble anti caking agent added so the crystals won't clump up. If excess aqueous lead (II nitrate is added to a 5.0 g sample of commercially sold sodium hydroxide 12.7 g of lead (II) hydroxide are recovered through filtration . What is the % purity of the sample of sodium hydroxide ?

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 .