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Chemistry 172
Quiz 1
c = 3.00 x 108 m/s
h = 6.626 x 10-34 J x s
Please circle any numerical answers.
1)
J = kg x m2/s2
c


14
Hz. What is
3.00 x 108 m/s
 6.40 x 10-7 m
14 -1
4.688 x 10 s
Which has the largest frequency, ultraviolet or infrared electromagnetic radiation?
ultraviolet
3)
E = -2.178 x 10-18J x (Z2/n2)
The laser beam used in eye surgery to repair detached retinas has a frequency of 4.688 x 10
the wavelength of this electromagnetic radiation?

2)
Name ____Key 10:00 am_____
Dr. Broekemeier
infrared
Consider an electron moving from orbital n = 2 to n = 5:
a) Will energy be emitted or absorbed for this transition?
emitted
absorbed
b) Calculate the actual energy change associated with this transition.
𝛥𝐸 = −2.189 𝑥 10−18 𝐽
1
1
− 2 = 4.57 𝑥 10−19 𝐽
2
5
2
c) What is the wavelength of this emitted light?
E  h  h
c

Rearrange to  =
hc
6.626 x 10-34 Js x 3.00 x 108 m/s
=
= 4.42 x 10-6 m
-20
E
4.575 x 10 J
4)
The frequency of a wave with wavelength 540 nm is ______the frequency of a wave of wavelength 790 nm.
( greater than
equal to
less than )
5)
The energy of electromagnetic radiation with a wavelength of 540 nm is _______ the energy of a wavelength of
790 nm.
(
greater than
equal to less than )
6)
What new idea did the photoelectrical effect suggest?
a) electrons have wave properties
c) light travels at a constant speed in a vacuum
7)
b) electromagnetic radiation has particle properties
d) the hydrogen atom has circular orbitals
Describe what the emission spectra of a hydrogen atom looks like compared to that of white light and report
what this indicated about the energy of the electrons around the hydrogen atom.
White light has all of the colors and therefore wavelengths present. The emission spectrum of
hydrogen had only certain colors and thus certain wavelengths present.
Because wavelength is related to energy, this indicated that there were only certain energies of
light emitted. This indicated that there were only defined energy levels for an excited atom and
the electrons could only be at certain energy levels.
8)
Draw an x,y,z axis and sketch a 3dxy orbital.
There should be 4 equal lobes in the x y plane. The lobes should not be on the x y axis, but at
a point in the middle.
9)
In atoms other than the hydrogen atom, the 2s orbital is at a lower energy than the 2p orbitals. This is because
electrons in the 2s orbital can get closer to the nucleus, a phenomena known as
___penetration______.
When the 2s electrons get in between the nucleus and the 2p electrons, the 2p electrons are
___shielded____ from the attractive force of the nucleus.
10)
l is the ( principal
magnetic
angular momentum
provides information on (
11)
orientation
electron spin
)
b) 2pz and 3pz
c) 3dxy and 3dxz
d) 3s and 4s
Which of the following is proportional to the probability that an electron can be found at a
particular point in space?
a) Ψ
13)
shape
In an atom other than the hydrogen atom, which of the following orbital pairs are degenerate?
a) 2px and 2s
12)
size
angular spin ) quantum number and
b) λ
c) Ε
d) Ψ2
e) Η
f) ν
What is the electronic configuration of indium (In)? Do not use the shorthand notation employing the noble gas
in brackets.
1s22s22p63s23p64s23d104p65s24d105p1
14)
How many valence electrons does selenium (Se) have?
6 (those in the 4s and 4p orbitals)
15)
How many electrons have the designation ml = -1 in bromine? 7 or 8
Electronic configuration is 1s22s22p63s23p64s23d104p5
There is an ml = 1 when l = 1 and 2 (the p and d orbitals) in this example.
There is an ml in 2p, 3p, 3d, and 4p. There are two electrons in each, except potentially the 4 p, which
may only have one.
16)
Provide a cation and an anion that are isoelectronic with argon.
+
2+
2Common choices: K , Ca , S , Cl