CHAPTER 6 Flashcards
A straight pencil that appears to be bent in a glass of water, is evidence that light is _____________ and indicates that light behaves as a _____________.
refracted, wave
reflected, wave
reflected, particle
refracted, particle
refracted, wave
A beam is produced and its passage through two slots reveals many bands on a detector screen. From this experiment, we conclude that the beam is:
a wave, since we have observed diffraction.
made of particles, since we have observed reflection.
a wave, since we have observed reflection.
made of particles, since we have observed diffraction.
a wave, since we have observed diffraction.
Which statements about waves are true?
The distance between two crests is a measurement of wavelength. The frequency of a wave is the number of times a crest passes a point per second. The amplitude of the wave is the half the distance from trough to crest.
The distance between a crest and a trough is a measurement of wavelength. The frequency of a wave is the number of times a crest passes a point per second. The amplitude of the wave is the half the distance from trough to crest.
The distance between two crests is a measurement of wavelength. The frequency of a wave is the number of times a crest passes a point per minute. The amplitude of the wave is the half the distance from trough to crest.
The distance between two crests is a measurement of wavelength. The frequency of a wave is the number of times a crest passes a point per second. The amplitude of the wave is the distance from trough to crest.
The distance between two crests is a measurement of wavelength. The frequency of a wave is the number of times a crest passes a point per second. The amplitude of the wave is the half the distance from trough to crest.
For any wave, its speed is equal to:
C
hν
hC/λ
λν
λν
Using a bar of chocolate and a microwave oven, a student estimates the wavelength of microwaves in the oven to be 14.4 x 10-2 m. Given that the speed of light is 3.0 x 108 m/s, the estimated frequency of the microwaves is:
2.1 x 109 Hz
60 Hz
2.1 x 109
60
2.1 x 109 Hz
FM-Mendeleev, an FM radio station, broadcasts at a frequency of 9.51 x 107 Hz. The wavelength of these radiowaves would be:
3 x 10-8 m
- 15 m
- 15 Hz
- 32 m
3.15 m
For light passing through two slits, whose slits are approximately equal to the wavelength of light, after the light has passed through those slits, on a screen, we would see _______ bands because of ___________.
multiple, diffraction
two, diffraction
multiple, refraction
two, refraction
multiple, diffraction
Descrete line spectra are observed for individual atoms of sodium. This observation indicates that:
light must be quantized.
the electrons in sodium transition between descrete energy levels.
Planck’s constant is 6.62 x 10-34 Js.
the speed of light is 3 x 108 ms-1
the electrons in sodium transition between descrete energy levels.
Which statement about the photoelectric effect is true?
There is a minimum threshold frequency of light, below which electrons are not ejected. Light is quantized as photons, where Ephoton = hν.
There is NO minimum threshold frequency of light, below which electrons are not ejected. Light is quantized as photons, where Ephoton = hν.
There is a minimum threshold intensity of light, below which electrons are not ejected. Light is quantized as photons, where Ephoton = hλ.
Light is quantized as photons, where Ephoton = hλ.
There is a minimum threshold frequency of light, below which electrons are not ejected. Light is quantized as photons, where Ephoton = hν.
According to DeBroglie, everything has an associated wavelength, according to the formula, λ = h/[mv].
h = 6.63 x 10-34 Js. The wavelength of a 0.2 kg baseball travelling at 30 m/s would be:
5 nm
- 63 x 10-34 nm
- 1 x 10-25 nm
- 1 x 10-34 nm
1.1 x 10-34 nm
Which of the following statements about the classic double slit experiment with electrons is correct?
A diffraction pattern is observed, indicating electrons behave as waves, and individual spots on the screen, indicate that electrons are particles.
A diffraction pattern is observed, indicating electrons behave as particles, and individual spots on the screen, indicate that electrons are waves.
A diffraction pattern is observed, just like in classic experiments involving light, indicating electrons behave as waves and are not particles.
none of these
A diffraction pattern is observed, indicating electrons behave as waves, and individual spots on the screen, indicate that electrons are particles.
Which statement best decribes our current understanding of the behaviour of electrons in atoms?
Electrons behave as waves in one dimensional space and produce standing waves of quantized energy levels.
Electrons behave as waves in three dimensional space and produce standing waves of quantized energy levels. Such three dimensional wave standing waves are special only for electrons and have no model or counterpart in the real world.
Electrons behave as waves in three dimensional space and produce standing waves of quantized energy levels.
Electrons produce standing waves of quantized energy levels, but we have no way of modelling what such waves would look like.
Electrons behave as waves in three dimensional space and produce standing waves of quantized energy levels.
In terms of electronic structure, 2p means that we are referring to:
none of these
Principal Quantum Number 2 and the p orbital.
Principal Quantum Number p and the 2nd subshell.
Principal Quantum Number 2 and the p subshell.
Principal Quantum Number 2 and the p subshell.
The maximum number of electrons held in the s and p subshells are respectively:
2 and 2
6 and 2
2 and 6
6 and 6
2 and 6
The number of orbitals in subshells s, p, d, and f, are respectively:
4, 6, 10, 14
2 in each type of subshell
1, 3, 5, 7
none of these
1, 3, 5, 7
Which ions with a +1 charge and a -2 charge have, repectively, the electron configuration 1s22s22p63s23p63d104s24p6?
Rb+ and Se2-
Sr+ and Br-
Se2- and Rb+
Kr+ and Kr2-
Rb+ and Se2-
Which combination of atoms would be expected to all have a half-filled s subshell?
Ne and Ar
Na and Rb
F and Cl
Na and Mg
Na and Rb
Atoms of which group in the periodic table have a valence shell electron configuration of ns2np3?
Group 15
Group 1
Group 18
Group 16
Group 15
Which statement about ionization energy is true?
First ionization energy measures the amount of energy, in kJ/mol, that is needed to remove an electron from a neutral atom.
First ionization energy measures the amount of energy, in kJ/mol, that is needed to remove an electron from an already ionized atom.
First ionization energy measures the amount of energy, in kJ/mol, that is needed to add an electron to a neutral atom.
First ionization energy measures the amount of energy, in kJ/mol, that is needed to add an electron to an already ionized atom.
First ionization energy measures the amount of energy, in kJ/mol, that is needed to remove an electron from a neutral atom.
The large difference between the ionization energies of hydrogen and helium would best be explained because:
helium has a larger nuclear charge than hydrogen and the electron distance has not changed much.
helium has a larger nuclear charge than hydrogen and the electron distance is very much smaller.
helium has a smaller nuclear charge than hydrogen and the electron distance has not changed much.
helium has a smaller nuclear charge than hydrogen and the electron distance has substantially increased.
helium has a larger nuclear charge than hydrogen and the electron distance has not changed much.
As we progress across a period in the Periodic Table, the general trend is an increase in ionization energy due to:
an increase in nuclear charge.
a decrease in nuclear charge.
an increase in shell number and therefore distance.
none of these
an increase in nuclear charge.
As we progress across Period 2 of the Periodic Table, we see a general increase in ionization energy. One dip in ionization energy that bucks the trend, is seen when progressing from Be to B. This is because:
Be has a full 2s subshell, whereas B has a single electron in the 2p subshell that is higher in energy than those in the 2s.
Be has a full 2p subshell, whereas B has a single electron in the 2s subshell that is higher in energy than those in the 2p.
B has a much stronger nuclear charge than Be.
Be has a much stronger nuclear charge than B.
Be has a full 2s subshell, whereas B has a single electron in the 2p subshell that is higher in energy than those in the 2s.
As we progress down a group in the Periodic Table, the major effect seen is a decrease in first ionization energy because:
each successive member in the group has a much lower nuclear charge.
each successive member in the group has a much higher nuclear charge.
each successive member in the group begins a new shell, some greater distance from the nucleus.
each successive member in the group begins a new shell, some smaller distance from the nucleus.
each successive member in the group begins a new shell, some greater distance from the nucleus.
The dramatic difference in ionization energies of Ne and Na is best explained by:
Distance: Sodium’s outermost electron is in the 3s subshell, whereas neon’s outermost electrons are in the 2p subshell.
Distance: Sodium’s outermost electron is in the 3p subshell, whereas neon’s outermost electrons are in the 2s subshell.
The nuclear charge of sodium is greater than the nuclear charge of neon.
The effective charge “seen” by the ionizable electron in sodium is more than that of neon
Distance: Sodium’s outermost electron is in the 3s subshell, whereas neon’s outermost electrons are in the 2p subshell.
