Chemistry Ch. 5 Practice Test
How many valence electrons are present in cesium? Write the electron configuration of cesium if the atomic number is 55.
1 valence electron electron configuration: [Xe] 6s .
State the drawbacks of Rutherford's nuclear atomic model.
1. lacks details about how electrons are arranged around the nucleus 2. doesn't explain why certain electrons are more reactive than others 3. doesn't explain why the negatively charged electron in an atom are not pulled into the atom's positively charged nucleus
Calculate the wavelength of a body pf mass 88.0 mg and moving with a velocity of 50.0 m/s. The value of Planck's constant is 6.626 X 10 J x s
1.51 X 10 m
A part of visible light has frequency 7.90 X 10 s-1. Calculate its wavelength if the velocity of light is 3.00 X 10 m/s.
3.80 X 10 m
Define a photon. What is the formula used to calculate the energy of a photon?
A particle of electromagnetic radiation with no mass that carries a quantum of energy. Ephoton = hv
Why does a piece of iron appear red when heated sufficiently and blue at a higher temperature?
A piece of iron appears red when heated sufficiently and blue at a higher temperature because the kinetic energy increases when heated.
What is meant by continuous electromagnetic spectra?
A spectrum is formed due to the dispersion of light when it is passed through a prism. It is called continuous if the dispersion of light is without any interruptions in with.
A photon is emitted from an atom with an energy of 4.25 X 10 J. What is the wavelength of the photon? A. 467 nm B. 2.73 X 10 m C. 1.28 X 10 m D. 6.42 X 10 m
A.
Which diagram shows a wave with the highest amplitude? A. B. C. D.
A.
Which is the correct electron dot diagram for the element Silicon (Si)? A. B. C. D.
A.
Which is the frequency of the wave shown? A. 2 Hz B. 2 secs C. 0.5 Hz D. 3
A.
Which is the most probable location for an electron in this orbital? A. B. C. D.
A.
Which label identifies the wavelength of the wave shown? A. B. C. D.
A.
Predict how the wavelength and frequency of a wave would change if the amount of energy it carried was increased.
As energy increases, the frequency of the wave also increases. This causes more waves to pass by a given point in a certain amount. Thus, each wavelength must be smaller.
Summarize the relationship between wavelength, frequency, and energy of a wave.
As the amount of energy carried by a wave increases, the individual waves get closer together, increasing their frequency, but decreasing their wavelength.
Which rule for filling of orbitals by electrons on the element Silicon is being violated in the orbital diagram shown? Justify your answer.
Aufbau principle; states that electrons must fill in the orbital with the lowest amount of energy before filling any orbitals with a greater amount of energy.
Use Plank's constant, 6.626 X 10 , to solve the following: What is the amount of energy carried by a photon that has a frequency of 5.71 X 10 Hz? A. 525 nm B. 3.78 X 10 J C. 1.14 X 10 J D. 8.62 X 10 J/s
B.
Which diagram shows a wave with the highest wavelength? A. B. C. D.
B.
Which element has the electron configuration 1s 2s 2p 3s 3p 4s 3d ? A. Titanium (Ti) B. Chromium (Cr) C. Sulfur (S) D. Selenium (Se)
B.
Which is the correct electron dot diagram for the element Fluorine (F)? A. B. C. D.
B.
Which is the correct number of valence electrons in the element of Sulfur (S)? A. 16 B. 6 C. 2 D. 4
B.
Which is the frequency of the wave shown? A. 8 sec B. 4 sec C. 0.125 Hz D. 0.5 Hz
B.
Which label identifies the amplitude of the wave shown? A. B. C. D.
B.
Which type of orbital is shown? A. s B. p C. d D. f
B.
In Bohr's description of the hydrogen atom's spectrum, the emitted radiations lie in the ________ series if the electron drops from infinity to level two.
Balmar
Which label identifies the trough of the wave shown? A. B. C. D.
C.
Which type of orbital is shown? A. s B. p C. d D. f
C.
Which type of wave has a wavelength of approximately 10 meters? A. microwaves B. ultraviolet light C. gamma rays D. AM radio
C.
State the importance of atomic emission spectra.
Consists of a number of bright lines separated by dark lines. These lines in the atomic emission spectra of the elements can be used to identify them.
What is the frequency of a light wave with a wavelength of 680 nm? A. 2.04 X 10 Hz B. 2.04 s C. 2.27 X10 Hz D. 4.41 X 10 Hz
D.
Which diagram shows a wave with the highest frequency? A. B. C. D.
D.
Which is the correct electron configuration for the element Molybdenum (Mo)? A. 1s 2s 2p 3s 3p 4s 3d B. 1s 2s 2p 3s 3p 4s 3d 4p 5s C. 1s 2s 2p 3s 3p 4s 4d 4p 5s 5d D. 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d
D.
Which is the correct number of valence electrons in the element Gallium (Ga)? A. 13 B. 31 C. 1 D. 3
D.
Which of these elements has 5 valence electrons? A. Boron (B) B. Rubidium (Rb) C. Vanadium (V) D. Arsenic (As)
D.
Which type of wave has a frequency of approximately 10 hertz? A. AM radio B. ultraviolet light C. x-rays D. TV< FM radio, cell phone
D.
Explain why it is only possible for two electrons to exist in the same orbital.
Electrons have a spin. In any given orbital, only 2 electrons can exits because one will spin upward while the other spins downward. A pair of electrons can only spin if they are in opposite directions.
An orbital forms the boundaries where electrons must be contained.
False
An s orbital is in the shape of a dumbbell.
False
In the visible light spectrum, red light has a greater frequency than violet light.
False
The Heisenberg uncertainty principle states that it is impossible to detect the position of an electron or velocity of an electron.
False
The number of electrons in an orbital depends on the orbital's shape.
False
[Kr]5s 4d 5p is the correct electron configuration for the element Bromine.
False
Which rule for the filling of orbitals in the element Phosphorus is being violated in the orbital diagram shown? Justify your answer.
Hund's rule; single electrons must occupy the orbitals within the same energy level and type of orbital before two electrons are allowed to occupy the same orbital
Why is it impossible to measure both the position and the velocity of an electron at the same time with accuracy?
It will disturb the electron and mess with the position and velocity.
Explain what is wrong with this electron dot diagram for the element Nitrogen (N)?
Only valence electrons are shown in a dot diagram and no more than 2 electrons can be on one side of the element symbol
How is light produced in neon signs?
Passing electricity through a tube filled with neon gas. Neon atoms absorb energy and become excited. This releases energy to emit light.
The ________ ___________ principle states that a maximum of two electrons may occupy a single atomic orbital, but only is the electrons have opposite spins.
Pauli Exclusion
Which rule for the filling of orbitals by electrons in the element Magnesium is being violated? Justify your answer.
Pauli exclusion principle; if 2 electrons occupy the same orbital, they must have opposite spins.
Write the noble gas form of the electron configuration and the electron dot structure of selenium and phosphorus.
Selenium: [Ar]4s 4p Se Phosphorus: [Ne]3s 3p P
Use the model of the atom shown to identify the correct element. Write the electron configuration and orbital diagram for this element.
Si 1s 2s 2p 3s 3p
Write the noble gas form of the electron configuration of the electron dot structure of sodium and oxygen.
Sodium: [Ne]3s . Na Oxygen: [He]2s 2p . O
A student records the following electron configuration for the element Arsenic (As). Evaluate this student's answer.
The "d " should be proceeded by a ; although the first set of d-block elements are in the fourth period, these electrons are actually contained in the third energy level due to the overlapping of energy levels and orbitals.
Explain the dual nature of an electron.
The dual nature of an electron states that an electron has characteristics of a particle as well as a wave.
What is meant by atomic emission spectra?
The set of the frequencies of the electromagnetic waves emitted by the atoms of the element upon excitation.
What is the significance of the wave function?
The wave function is the solution of the Schrodinger wave equation. The equation is related to the probability of finding an electron within a particular volume of space around the nucleus.
Although the precise location of an electron cannot be determined, it is possible to determine the probability that an electron will occupy a certain region around the nucleus.
True
An element can be identified by the characteristic bright-line atomic emission spectrum it can produce.
True
As the amount of energy carried by a wave decreases, its wavelength increases.
True
Energy is found only in specific discrete amounts, called quanta.
True
Six electrons can exist in a p-orbital.
True
The emission of photons from the surface of a metal depends in the frequency of incident light, not on the intensity of light.
True
The maximum number of allowed valence electrons in any atom is 8.
True
The photoelectric effect describes the emission of electrons from a metal's surface when light at a specific frequency shines on it.
True
The unit for measuring the energy of a wave is Hertz.
True
There are a total of 5 different types of d-orbital.
True
Valence refers to the total number of electrons that exist in the orbitals that occupy the outermost energy level of an atom.
True
The arrangement of electrons in an atom is called the __________ ______________ of an atom.
electron configuration
What is the ground state electron configuration of chlorine and the number of valence electrons in it?
ground state configuration: 1s 2s 2p 3s 39 . 7 valence electrons
The minimum amount of energy that can be gained or lost by an atom is known as a __________.
quantum
List and define the characteristics of a wave.
wavelength: points on a wave frequency: number of waves in a set time amplitude: the wave's height speed: all electromagnetic waves
