Chemistry exam

Which combination best represents the mass and the charge of a proton?

1 amu;positive

Use tab to navigate through all the objects Press space or enter to select or deselect the object Select the correct electron representations from the choices below.

1s2 2s2 2p6 3s2 3p3 1s2 2s2 2p6 3s2 3p6 4s2

Which most likely describes the atomic number of an element?

A.28

What properties of an electron are described by its set of quantum numbers?

A.energy and location

In the Bohr model of the atom, where are electrons located?

A.in energy levels in space around the nucleus

Which of the following is described by an azimuthal quantum number?

A.orbital shape

Which atomic theory did Ernest Rutherford propose?

A.the nuclear model of an atom

What atomic theory is quantum mechanics associated with?

A.the orbital model of an atom

What did the cathode ray tube experiment demonstrate?

A.the presence of electrons in an atom

An atom emits a photon of light. What could cause this to happen?

D.an electron releases energy as it moves to a lower energy level

Oxygen has eight electrons. How many electrons can be located in each of its orbitals?

A.2

An atom of hydrogen-2 contains one proton, one neutron, and one electron. Which particle(s) identify the atom as hydrogen?

A.the proton

What must be true about two electrons in the same orbital?

A.they must have different magnetic spin numbers

What does the word "atom" mean?

B. indivisible

Which combination best represent the mass and charge of a neutron?

B.1 amu;neutral

Fluorine-19 has an atomic number of 9 and a mass number of 19. How many neutrons does an atom of fluorine-19 contain?

B.10

One atom of iron contains 26 protons, 30 neutrons, and 26 electrons. Which of the following would be possible for another atom of iron?

B.26 protons,28 neutrons,and 26 electrons

In the orbital diagram, if it were written correctly using the same number of electrons, what element would it be describing?

B.O

A student is making a single graph to show the emission spectrum of an element in terms of both frequency and wavelength. Which of the following should be true about the axes drawn by the student?

B.The numbers for wavelength would increase from left to right and the numbers for frequency would increase from right to left.

Who proposed the plum pudding model of the atom?

B.Thomson

Which atom has the greatest mass?

B.an atom with 8 protons,8 neutrons,and 8 electrons

Which aspects of John Dalton's atomic theory are still relevant to modern atomic theory?

B.atoms of different elements combine in simple,whole-number ratios to form chemical compounds

An atom of carbon-14 contains six protons, eight neutrons, and six electrons. Which will an atom of carbon-12 contain?

B.six protons,six neutrons, and six electrons

What did the gold foil experiment demonstrate?

B.the density of mass in the nucleus

How many quantum numbers are assigned to each electron in an atom?

C.4

The atomic number of lead is 82. Its mass number is 207. How many protons, neutrons, and electrons does this atom of lead contain?

C.82 protons,125 neutrons,and 82 electrons

The mass number of one form of plutonium is 244. Which combination of protons and neutrons is possible for this form of plutonium?

C.94 protons,150 neutrons

The mass of a proton is closest to the mass of which particle?

C.a neutron

Which of the following describes the arrangement of electrons in the Bohr model of the atom?

C.arranged in circular orbits

Which of the following statements is associated with the quantum theory of atomic structure?

C.each electron has a defined amount of energy that can be defined by a set of numbers

Which of the following can happen to an electron according to the Bohr Model?

C.it can move to a different energy level only if it gains or loses a specific amount of energy

What does the Pauli exclusion principle state?

C.no two electrons in a given atom can have the same set of quantum numbers

Which particle is mostly likely to carry electromagnetic force?

C.photon

In the photoelectric effect, light causes ejection of an electron from a substance. A student working on a demonstration of the photoelectric effect sets the light to an arbitrary frequency. When he activates the light and nothing happens, he claims that the apparatus is broken. What has he failed to consider?

C.that light can be described as particles of light of distinct energy,and that the frequency chosen was not consistent with the energy needed to see a result

What was the major difference between Dalton's model of the atom and the plum pudding model of the atom?

C.the addiction of electrons to the model of the atom

What was one contribution of the early Greek philosophers regarding atomic theory?

C.the description of units called atoms

A student is making a diagram to illustrate the hydrogen atom according to the Bohr model. She wants to show how the model correlates to the hydrogen emission spectrum. Which of the following should be true about the diagram drawn by the student if the diagram is to be accurate?

C.the diagram should show several energy levels with arrows pointing in the direction from the higher to the lower levels to show the movement of hydrogen's one electron in creating the emission lines.

What atomic theory did Niels Bohr propose?

C.the orbital model of an atom

Which of the following describes the relationship between frequency and wavelength for electromagnetic radiation?

C.they are inversely proportional to one another

Which characteristic(s) of a wave of electromagnetic radiation would be sufficient to calculate the speed of light?

C.wavelength and frequency

Is it possible to increase the wavelength of light by varying frequency? Why or why not?

C.yes,to increase wavelength,frequency is decreased

What are the two ways that physicists describe light?

D. as a particle and a wave

Which describes the number of protons in the atom of a particular element?

D.atomic number

What information was added to Dalton's theory as it was refined?

D.atoms are composed of a subatomic particles

What was different about the atomic theory proposed by Niels Bohr?

D.electrons energy levels related to theirs orbits

Which of the following is described by a principal quantum number?

D.energy level

The emission spectrum of an element

D.is different from any other element's absorption spectrum

Where is most of the atom's mass located?

D.nucleus

When energy is added to an atom, which of the following events is most likely to occur?

D.some of the atom's electrons move to a higher energy level

How are wavelength and frequency related to one another?

D.they vary inversely with one another

Electric current is passed through a cold gas in a sealed glass cylinder. Excited electrons at different energy levels fall to lower energy levels. Order the electrons by the amount of energy they emit, from greatest to least.

Greatest Energy 1.Drops from energy level 6 to energy level 2 2.Drops from energy level 6 to energy level 3 3.Drops from energy level 5 to level 3 4.Drops from energy level 5 to energy level 4

Scientists now believe that light is both a wave and a particle. Classify the following characteristics of light as a property of a wave or a property of a particle.

Properties of light as a wave can be absorbed or reflected can bend or diffract travels at a speed of 3,000,000 kilometers per second Properties of light as a particle has mass carries a quanta of energy can knock electrons out of metals