A sample of polystyrene prepared by bulk polymerization at 60°C using radioactive 14C-AIBN as initiator was found to have a number average molar mass (Mn) of 1000 kg/mol and a radioactivity of 6 x 103 counts/(s. g). Given that the 14C-AIBN has a radioactivity of 6x109 counts/(s. mol). Determine the mode of termination that operated during preparation of the polystyrene sample. (Note: bulk polymerization means that no solvent is used, and the reaction is carried out in pure liquid monomer).

Nitric oxide (no) can be formed from nitrogen, hydrogen and oxygen in two steps. in the first step, nitrogen and hydrogen react to form ammonia: n2(g) + 2 h_2(g) rightarrow 2 nh_3 (g) delta h = -92. kj in the second step, ammonia and oxygen react to form nitric oxide and water: 4 nh_3(g) + 5 o_2(g) rightarrow 4no(g) + 6 h_2o(g) delta h = -905. kj calculate the net change in enthalpy for the formation of one mole of nitric oxide from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .

Blank allows you to do calculations for situations in which only the amount of gas is constant a)boyle's law b)combined gas law c)ideal gas law d)dalton's law

21. consider the following chemical reaction: n2+ o2 2 no if 10.0 g of n2 reacts with excess oxygen then how many grams of no can be formed? a) 10.7 g b) 21.4 g c) 32.9 g d) 42.8 g page 4 of 8