Dimensional Analysis and Atomic Structure

Question 1

If the density of mercury is 13.5 g/cm3, what is the volume of a 50.0 lb sample of mercury? (1 kg = 2.2 lb, approximately.)

Answer 1

1700 cm3

Question 2

If the diameter of a mercury atom is 310 pm, how many mercury atoms would be needed to make a 1-cm line of atoms?

Answer 2

3.2x10^7

Question 3

How many electrons does a Zn2+ ion have?

Answer 3

28

Question 4

How many neutrons does a 14C atom have?

Answer 4

8

Question 5

Chlorine exists mostly as two isotopes, 35Cl (35.0 amu) and 37Cl (37.0 amu). What is the relative abundance of these isotopes?

Answer 5

~75% 35^Cl and ~25% 37^Cl

Question 6

What is the appropriate notation for an atom or ion that has 8 protons, 9 neutrons, and 10 electrons?

Answer 6

17^O2-^

Question 7

What was the important outcome of Millikan’s famous oil drop experiment?

Answer 7

It was used to determine the charge of an electron.

Question 8

What are cathode rays, which Thomson studied in his famous cathode ray experiments?

Answer 8

electrons

Question 9

In Rutherford’s gold foil experiment, why were some of the alpha particles deflected back toward the source?

Answer 9

They were bouncing off nuclei, which are positively charged and more massive than alpha particles.

Question 10

The mass of 12C is exactly 12 amu, and the mass of 13C is about 13 amu. The atomic weight of C (on the periodic table) is 12.01. If you have 1000 naturally occurring C atoms, approximately how many of them have a mass of 12.01 amu?

Answer 10

0