I will start using a few multiple choice from the Test Bank for the text for practice questions. Some of the questions on your quizzes may be similar to these. ---MD

1. Which of the following types of radiation has the lowest relative energy ? Which one has the highest relative energy ?

2. What is the frequency of yellow light having a wavelength of 562 nanometers (nm) ?

a) 5.33 x 10E+14 Hz b) 1.87 x 10E+14 Hz c) 1.18 x 10E-27 Hz d) 5.33 x 10E+5 Hz

3. What is the energy of a mole of photons of orange light with a wavelength of 585 nm?

a) 1.20 x 10E-52 j/mol b) 2.78 x 10E+28 j/mol c) 2.04 x 10E+5 j/mol d) 7.41 x 10E-28 j/mol

4.What is maximum number of atomic orbitals that can have the quantum numbers n =4, l = 3 and m(l) = -2 ?

a) 0

b) 1

c) 3

d) 5

e)7

5. When l = 3, what set of atomic orbitals is designated ?

a) s

b) p

c) d

d) f

e) g

6. What type of atomic orbital is designated n = 3, l = 2 and m(l) = 0 ?

a) 2s

b) 3s

c) 2p

d) 3p

e) 3d

7. Which of the following set of quantum numbers is not allowed ?

a) n = 3, l = 3 and m(l) = 3

b) n = 3, l = 1 and m(l) = 0

c) n = 3, l = 0 and m(l) = 0

d) n = 4, l = 3 and m(l) = -2

e) n = 4, l = 2 and m(l) = +2

8. When l = 2, the possible values of m(l) are

a) 0

b) +1,+2,+3

c) +2,+1,0,-1,-2

d)+1,0,-1

e) none of these

9.According to the Bohr atomic theory, when an electron moves from one energy level to another one that is further from the nucleus

a) energy is absorbed b) energy is emitted c) light is emitted d) no energy change is observed e) photons are destroyed

10. The quantum number, m(l) represents the

a) number of valence electrons b) number of atomic orbitals c) shape of the orbital d) orientation of the orbitals e) momentum of the electrons.

11. Explain what is being described by the quantum numbers n, l and m(l) .

12 According to the quantum number rules discussed in this chapter, which of the following atomic orbitals types would not be possible? Briefly expain your reasoning

1p

2p

2d

3d

4d

3f

4f

5p

 

Answers:

1 Lowest relative energy = longest wavelength or lowest frequency = radio waves

Highest relative energy = shortest wavelength or highest frequency = gamma rays

2. a (1.00/ 562 x 10E-9m) x 3.00 x 10E+8 meters/sec = 5.33 x 10E+14 Hz

3. c (1.00/585 x 10E-9 m) x 3.00 x 10E+8 = 5.12 X 10E+14 Hz

5.12 x 10E+14 Hz x 6.62 x 10E-34 x 6.02 x 10E+23 =2.04 x 10E=5 joules/mole

4. b only one atomic orbital It would be desiginated a "4d" orbital.

5. d = f orbitals. There would be 7 corresponding to m(l) = -3,-2,-1,0,+1,+2,+3

6. e = 3d

7. a Since for n = 3, the possible "l" values are 0, 1 and 2 . 3 is not an "allowed " quantum number for l in this case.

8. c Allowed values of m(l) are all intergers from -l to +l or -2,-1,0,+1,+2

9. a

10. d orientation in space of the atomic orbital. For example the three m(l) values for "p" atomic orbitals give them geometric orientation along the three cartesian axis, x,y and z and are symbolized as p(x), p(y) and p(z) respectively.

11. The quantum number n describes the energy level of an atomic orbital. The larger the n value, the further away the atomic orbital is from the nucleus. The quantum number, l indicates the shape of the stomic orbital. you should rremember the shape and the orientation of the "s" and the three "p" orbitals. The quantum number, m(l) gives the geometric orientation of the orbital. An "s" orbital is spherical, the "p" orbitals are "dumb bell" shaped and pointing along the three axis, x, y and z; and so on.

12 . 1p is impossible If n = 1 the only possible l is 0 or "s". The quantum number, l is allowed all interger values up to n-1.

2d is impossible similar reasoning n = 2 , possible l values are 0 and 1 or "s" and "p" orbitals.

3f same problem n = 3 allowed l value are 0,1 and 2 or "s" ,"p" and "d" . An "f" orbital represents l = 3

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