Chem 1010 USU module 4 quiz

How are frequency and wavelength related?

The higher the frequency the shorter the wavelength.

What prompted early scientists to propose that the ray of the cathode ray tube was due to the cathode?

The ray was present regardless of gas, or even without a gas.

Why can't we see atoms?

We see with light energy and the wavelength of light is larger than the atom and is not reflected.

You cannot make a physical model of the atom because...

We see with light energy and the wavelength of light is larger than the atom and is not reflected.

Consider the various frequencies of the three photons emitted from the following three individual electron transitions in the figure below: n=3 to n=2; n=2 to n=1; n=3 to n=1. These transitions would produce three spectral lines in a spectroscope. If the energy spacing between the levels were equal, would this affect the number of spectral lines?

Yes, two otherwise separate lines would converge into a single more intense line.

Does it make sense to say that a textbook is about 99.9 percent empty space?

Yes. A textbook like all material things is made up of atoms, which are considered to be 99.9 percent empty space.

What does the following element description actually mean?hydrogen-2

a hydrogen with one neutron and one proton

The following statement describes which subatomic particle best? It does not have an electrical charge.

a neutron

If two protons and two neutrons are removed from the nucleus of the oxygen-16 isotope, a nucleus of which element remains?

carbon-12

Which of the following is not a property of an electron? fundamental component of atoms has a negative charge weighs approximately 9.1 × 10-31 kg charge changes depending on mass

charge changes depending on mass

What does the following element description actually mean?iron-57

iron with a mass number of 57

An atomic orbital ________.

is a three-dimensional region of space

Which experiences a greater effective nuclear charge, an electron in the outer shell of neon (atomic number 10) or an electron in the outer shell of sodium (atomic number 11)?

neon because of less inner shell shielding

It is relatively easy to pull an electron away from a potassium atom (K, atomic number 19), but very difficult to remove a second one because ________.

of a much greater effective nuclear charge

How many electrons are there in the third shell of sodium, Na (atomic number 11)?

one

Would you use a physical model or a conceptual model to describe the following: the brain; the mind; the solar system; the beginning of the universe?

physical; conceptual; physical; conceptual

The nucleus of an electrically neutral iron atom contains 26 protons. How many electrons does this iron atom have?

26

If an element has 15 protons and 16 neutrons and 15 electrons, what is the mass number of the element?

31

Which of the following statements about electrons is true?

All of these are true: Electrons are particles. Electrons behave like waves. Electrons in atoms can be excited by light energy. Electrons have a negative charge.

How can a hydrogen atom, which has only one electron, have so many spectral lines?

Because there is more than one energy level in a hydrogen atom.

Which loses its outermost electrons more easily: bromine, Br, or krypton, Kr?

Br

Which of the following atoms is the smallest? K Ca Br Ga As

Br

An atom emits electromagnetic radiation when an electron moves from a lower energy level to a higher energy level. True or False?

False

Which of the following does not describe a neutron?

It has a positive charge equivalent but opposite of an electron's. (DOES NOT DESCRIBE) It is much more massive than an electron. It is found in the nucleus of an atom. It has no charge.

What is a probability cloud?

It is a map of the likelihood of finding an electron within a given area.

Which of the following statements does not describe a proton? It is attracted to negatively charged electrical plates. It has a positive charge equivalent but opposite of an electron's. It orbits around the nucleus of an atom. It is much more massive than an electron.

It orbits around the nucleus of an atom.

Which of the following experiments helped to determine the charge of an electron and (indirectly) its mass?

R. Millikan's oil drop experiments

From which of the following atoms would removing an electron be the easiest? Xe Cd Sr I Rb

Rb