Name:
General Chemistry
Unit 2 Review-Atomic Theory
1. According to Dalton’s theory atoms can’t be created or destroyed.
Is this still true today? Explain. No, it is not true. In Dalton’s time technology for
splitting atoms was not yet developed.
2. According to Dalton’s theory all atoms of the same element are identical in mass,
size and properties. Is this still true today? Explain. Part of it is true. Atoms of
the same element have the same properties. In Dalton’s time no one knew about
isotopes. Isotopes of an element can vary in their size and mass because their
number of neutrons can vary.
3. List the 3 subatomic particles and tell the charge of each as you go.
Protons positive
electrons negative
neutrons neutral
4. List the 3 subatomic particles and tell the location of each as you go.
Protons nucleus
electrons electron cloud
neutrons
nucleus
5. Why is Cl-37 heavier than Cl-35?
It is heavier because it has 2 more neutrons than Cl-35.
6. Which element has 22 electrons and 24 neutrons?
Titanium
7. Write the nuclear symbol for zinc-65.
65
30 Zn
8. Write the hyphen notation for an element with 16 protons and 17 neutrons.
Sulfur-33
9. Draw a picture of an atom of
correct region of the atom.
27
Al showing all of the subatomic particles in the
13
13 protons
14 neutrons
13 electons
10. Which model of the atom described the atom as an indivisible sphere?
Dalton’s model of the atom
Name:
11. Which model of the atom showed electrons that were evenly dispersed throughout
the atom?
Thompsons’s plum pudding model
12. Which model of the atom shows the atom with a dense positively charged center?
Rutherford’s model
13. Which model describes electrons being in energy levels at varying distances from
the nucleus?
Bohr’s model of the atom
14. What factor determines the identity of a particular atom?
the atomic number ( number of protons)
15. What 2 major regions make up the atom?
The electron cloud and the nucleus
16. How many protons, neutrons and electrons are in Argon-37?
18 protons, 19 neutrons, 18 electrons
17. Write the hyphen notation for an element with 56 electrons and 82 neutrons.
Barium-138
18. Write the nuclear symbol for an element with 26 protons and 30 neutrons.
56
26Fe
19. Use the relative mass and % abundance data in the table below to calculate the
average atomic mass of nitrogen. Round your answer to 4 sig.figs.
Isotope
N-14
N-15
Number of
Protons
7
7
Number of
neutrons
7
8
Relative
Mass (u)
14.1120
15.1207
Percent
Abundance
99.64%
0.36%
14.11563 u
20. Use the relative mass and % abundance data in the table below to calculate the
average atomic mass of oxygen. Round your answer to 4 sig.figs.
Isotope
0-16
0-17
0-18
Number of
Protons
8
8
8
Number of
neutrons
8
9
10
Relative
Mass (u)
16.1280 u
17.1367 u
18.1454 u
Percent
Abundance
99.76%
0.040%
0.20%
16.132437 u
21. State the periodic law.
The repeating properties of the elements are a function of the atomic number.
22. Who is considered to be the father of the periodic table?
Dmitri Mendeleev
Name:
23. By which number are the elements on the periodic table arranged?
The atomic number
24. What is the family name of the elements in group 17?
halogens
25. How many valence electrons does bromine have?
7
26. What would be the charge on calcium if it were to ionize?
+2
27. Which is bigger, rubidium or sodium?
Rb
28. If oxygen were to ionize, which would be bigger, the atom (O) or the ion (O2-)?
The ion would be bigger.
29. Which element would have the higher ionization energy, potassium or bromine
Br
30. Is iridium a metal, nonmetal or metalloid?
Metal
31. What do we call ions with a negative charge?
anions
32. What do we call ions with a positive charge?
cations
33. Will fluorine form a cation or an anion when it ionizes?
anion
34. Describe the location of the representative elements?
They are in the s and p blocks.
35. Where are the actinides on the periodic table?
They are the second row under the periodic table in the f block.
36. Where are the lanthanides on the periodic table?
They are the first row under the periodic table in the f block.
37. Which family on the periodic table is as reactive as the alkali metals?
The halogens are.
38. How many valence electrons do the elements oxygen and sulfur have?
6
39. How many electron s will each ion have: Rb+, P3-, and I-?
Rb =36 P = 18 I = 54
40. How many electrons will each ion have: Ca2+, and O2-?
Ca = 18 O = 10
41. Which of the following elements is a transition metal: Na, Br, V, or Te
V
42. Which group contains only metalloids?
a. Al. Ga
b. Si, Ge
c. P, As
d. Al, Si, P
e. Ga , Ge , As
e
43. Which list has only nonmetals?
a. N, O, Cl b. I, Fe, Ca
c. Br, Mg, Cu d. U, Pa, Np
Name:
a
44. Which list has only actinides?
b. N, O, Cl b. I, Fe, Ca
c. Br, Mg, Cu d. U, Pa, Np
d
45.. Do metals tend to lose electrons or gain electrons when they ionize?
lose