Two representations of the distribution of electrons in the potassium atom are shown. Model 1 Model 2
1s22s22p63s23p64s1
An orange circle labeled upper K is surrounded by four concentric circles. The innermost circle has dots at the north and south positions. The second and third circles have eight dots, equally spaced, with dots aligning with those on the inner ring. The outer ring has one dot at the north position.
Which model is useful in showing the reactivity of potassium?
Neither model is able to show the reactivity of potassium.
Model 1 because it shows an electron in the 4s orbital.
Model 2 because it shows an electron in the outermost ring.
Both models because each shows an electron in the outermost shell.

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

Water is initially present in a state where its molecules are far apart. during a change of state, its molecules slow down. which change of state has most likely taken place? from a gas to a liquid from a liquid to a gas from a solid to a liquid from a gas to a plasma

Which terms are used to identify pure substances