Donald is making a model of a nitrogen atom. the box for nitrogen in the periodic table is shown. to represent a neutral atom, which of these must donald include in his model?
a) exactly 4 electrons
b) exactly 7 electrons
c) exactly 10 electrons
d) exactly 14 electrons

The isotonic saline solution described in part a is connected to an unknown solution via a semipermeable membrane, the unknown solution level drops. based on this information, what can be said about these two solutions?

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

Which of the following describes a situation where competition between producers exists