A chemist prepares a solution of nickel(II) chloride NICl2 by measuring out 315 umol of nickel(II) chloride into a 500ml volumetric flask and filling the flask to the mark with water. Calculate the concentration in umol of the chemist's nickel(II) chloride solution. Round your answer to 3 significant digits.

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 .