Identify the true statement. Choose one: A. The center material of our Solar System's protoplanetary disk developed into the Sun, while the series of surrounding dust, gas, and ice rings became planets. B. Volatile materials are those that melt only at high temperatures. C. Planetesimals that were larger than 1 km in diameter gravitationally pulled in all surrounding dust, ice, and smaller planetesimals to become asteroids. D. A stellar wind consists of the debris that is exploded out of a star as it "dies."

Amass of 100.0 g of solute is dissolved in water so that 850. ml of a 0.7500 m solution has been prepared. what is the molar mass of the solute?

Salicylic acid is a very important acid. it is used to synthesize the aspirin by treating with acetic anhydride. a 0.2015-g sample of salicylic acid was dissolved in a 100.00-ml volumetric flask, and the solution was diluted to the mark. a 10-ml aliquot of this solution was titrated with standard naoh (0.01130 + 0.2% n) to a phenolphthalein faint pink color end point at 19.81 ml. (a) (calculate the normality of the salicylic acid solution used in the titration. (b) assuming the salicylic acid is pure, what is the equivalent weight of the salicylic acid? practice problems for the final exam (continued) (c) (calculate the inherent error in the determination of the equivalent weight you calculated in part (b). use the following absolute errors in the equipment /glassware when calculating the inherent error. 5.00-ml pipet: + 0.02 ml 100-ml volumetric flask: + 0.08 ml analytical balance: + 0.2 mg 25-ml buret: + 0.03 ml

Aconcentrated solution of ammonia is 14.8m and has a density of 0.899g/l. what is the concentration of ammonia in this solution in weight percent (%w/w)?