Download Exam III Review

Name_________________________
Period____________
Exam III Review
Atomic Theory, History of the Atom, and Nuclear Chemistry
1. These 6 scientists were influential to atomic history. Draw and name their atomic models (if
they had one) and what part of the atom they are credited with discovering. Include
important experiments (such as the cathode ray tube, gold foil, and oil drop experiments)
and make sure you know what they learned from them!
Democritus –
Dalton –
J. J. Thompson –
Ernest Rutherford –
James Chadwick –
Robert Millikan –
Niels Bohr Schrödinger –
2. What are the 3 subatomic particles we know about today? What are their charges, and
where are they located in the atom.
3. What is an ion? Give me an example of an ion.
4. How many protons, neutrons, and electrons are found in each of the following:
8135Br13253I10746Pd3+
5828Ni+
p:
n:
e-:
p:
n:
e-:
p:
n:
e-:
p:
n:
e-:
Name_________________________
Period____________
5. An Iron atom is 1.72 angstroms (Å) wide. How many iron atoms would you have to stack end
to end to stretch the width of this piece of paper, 8.5 inches? (remember: 1 Å = 10-10 m and
1 inch = 2.54 cm)
6. Calculate the average atomic mass of this atom and identify the element.
Show all of your work for full credit.
Isotope
% Abundance
Mass (amu)
28X
92.21%
27.976
29X
4.70%
28.977
30X
3.09%
29.974
7. Write the nuclear equation that represents the alpha decay of americium-243.
8. The half-live of carbon-14 is 5730 years. If a sample contains 16.2 grams of carbon-14 and is
22,920 years old, how much carbon-14, in grams, was in the original sample?
9. What are the 3 types of radioactive decay? List their name, symbols, and what material you
need to block them from hitting you.
10. Radioactive decay
a. Occurs in unstable isotopes.
b. Is spontaneous.
c. Both a and b
d. Neither a nor b
11. Two isotopes of the same element may have different
a. Mass numbers and atomic numbers.
b. Numbers of protons and number of neutrons.
c. Mass numbers and numbers of neutrons.
d. Chemical properties.
Name_________________________
Period____________
12. Radiation
a. Can be used in food preservation.
b. Causes the disruption of cells in living tissue.
c. Can be useful in the treatment of cancer.
d. All of the above.
13. An atom is
a. A tiny, indivisible particle.
b. The smallest piece of matter.
c. The smallest particle of an element that retains the chemical identity of that element.
d. An artificially assembled unit that contains protons and electrons.
14. J.J. Thomson concluded that a cathode ray contains negatively charged particles by studying
how
a. The cathode ray produced a green spot on the fluorescent screen.
b. A magnetc field deflected the ray’s path.
c. The ray was deflected by electrical charged plates.
d. Both b and c.
15. Rutherford’s gold foil experiment indicated that
a. The nucleus of an atom occupies most of an atom’s volume.
b. Positive charges are dispersed throughout the atom.
c. Positive charges are concentrated in a very small core at the atom’s center.
d. Protons and neutrons are located in the nucleus.
16. Today scientists have determined that electrons
a. Move in the space around the nucleus.
b. Have a mass equal to the mass of protons.
c. Orbit the nucleus in a well-defined path.
d. Are electrically neutral.
17. Atoms of each element contain a unique number of
a. Neurons in their nuclei.
b. Protons in their nuclei.
c. Electrons in their nuclei.
d. All of the above.
18. The half-life of a radioactive isotope
a. Is the time it takes for one half of the sample to decay.
b. Is the time it takes for all of the sample to decay.
c. Is always more than 10,000 years for any given element.
d. Cannot be mathematically calculated.
NOTE: REMEMBER TO REVIEW YOUR LABS/NOTES/OULINES AND HOMEWORK AS WELL!