Question

37) What is the volume occupied by 4.00 g of O2 gas at STP? A) 2.8 mL B) 89.6 L C) 89.6 mL D) 5.6 L E) 2.8 L 38) Which of the followin g expressions is the correct equilibrium-constant expression for the following reaction? CO2 (s)+ 2H2 (g)CH3OH (g) A) [CH30H] (H2]2 CH3OH] co2 CH3OH] CO2H2)2 [CO2l(H212 [CH3OH ICO2l[H2] (CH3OH B) C) D) E) 39) The pH of a 0.25 M aqueous solution of hydrofluoric acid, HF, at 25.0 °C is 2.03. What is the value of Ka for HF? A) 2.0 x 10-9 B) 6.0 x 10-5 C) 3.5 x 10-4 D) 1.1 x 10-9 E) none of the above 40) A solution is prepared by dissolving 15.0 g of NH3 in 250.0 g of water. The density of the resulting solution is 0.974 g/ml. The molarity of NH3 in the solution is D) 3.53 M. A) 0.882 B) 0.00353 C) 3.24 E) 60.0