All Units

What is another name for the transition metals?

Group B elements

Each period in the periodic table corresponds to a

principal energy level

The modern periodic table is arranged in order of increasing atomic

number

Who arranged the elements according to atomic mass and used the arrangement to predict the properties of missing elements?

Dmitri Mendeleev

Which category includes the majority of the elements?

metals

Of the elements Pt, V, Li, and Kr, which is a nonmetal?

Kr

To what category of elements does an element belong if it is a poor conductor of electricity?

nonmetals

The atomic number of an element is the total number of which particles in the nucleus?

protons

Which subatomic particle plays the greatest part in determining the properties of an element?

electron

What are the Group 1A and Group 7A elements examples of?

representative elements

What causes the shielding effect to remain constant across a period?

electrons are added to the same principal energy level

Atomic size generally ____ as you move from left to right across a period

decreases

The metals in Groups 1A, 2A, and 3A ___ electrons when they form ions.

lose

By 1700, how many elements had scientists discovered and isolated?

13

Compared with the electronegativities of the elements on the left side of a period, the electronegativities of the elements on the right side of the same period tend to be

higher

Which statement correctly compares the relative size of an ion to its neutral atom?

the radius of the ion is bigger

What is a factor that contributes to the increase in ionization energy from left to right across a period?

an increase in the number of protons

Which group of the periodic table is known as the alkali metals?

1A

Which group of the periodic table is known as the noble gases?

8A

About what percent of elements is classified as metals

80%

How many electrons are there in the highest occupied energy level of atoms in Group 5A elements?

5

How many electrons does the ion Ca^2+ contain?

18

When an electron moves from a lower to a higher energy level, the electron

absorbs a quantum of energy

The shape (not the size) of an electron cloud is determined by the electron's

energy sublevel

What is the number of electrons in the outermost energy level of an oxygen atom?

6

In the Bohr model of the atom, an electron in an orbit has a fixed

energy

How does the speed of visible light compare with the speed of gamma rays, when both speeds are measured in a vacuum?

the speeds are the same

Which color of visible light has the shortest wavelength?

violet

How does the energy of an electron change when the electron moves closer to the nucleus?

it decreases

How are the frequency and wavelength of light related?

they are inversely proportional to eachother

Emission of light from an atom occurs when an electron

drops from a higher to a lower energy level

The atomic emission spectra of a sodium atom on Earth and of a sodium atom in the sun would be

the same

What is the approximate energy of a photon having a frequency of 4 x 10^7 Hz? (h = 6.626 x 10^-34 J x s)

3 x 10^-26 J

Which variable is directly proportional to frequency?

energy

How do the energy differences between the higher energy levels of an atom compare with the energy differences between the lower energy levels of the atom?

They are smaller in magnitude than those between lower energy levels.

What are quanta of light called?

photons

Bohr's model could only explain the spectra of which type of atoms?

single atoms with one electron

According to the Heisenberg uncertainty principle, if the position of a tiny moving particle is known, the

velocity cannot be determined

The wavelike properties of electrons are useful in

magnifying objects

What element in the second period has the largest atomic radius?

lithium

Across a period, electrons are added to the same

principal energy level

The shielding effect is _______ for all elements in a period

constant

First ionization energy generally ______ from top to bottom within a group

decreases

Define electronegativity

ability of an atom to attract electrons

Define ionization energy

the energy required to remove an electron from an atom

Which group of the periodic table is known as the alkaline earth metals?

2A

Which group of the periodic table is known as the halogens?

7A

Which group of the periodic table is known as the pnictogens?

5A

Which group of the periodic table is known as the chalcogens?

6A

The inner transition metals are the elements that appear

Below the main body of the periodic table

In the electron configurations of the representative elements, the highest occupied s and p sublevels are

partially filled

Of the elements Pd, W, As, and K, which is a metalloid

As

Which elements are metalloids?

Bi, Si, As, Te, Ge, Sb

What contributes to the increase in atomic size within a group in the periodic table as the atomic number increases?

more shielding of the electrons in the highest occupied energy level

What happens when an atom loses electrons?

Cations form

For human purposes, the lanthanides are particularly useful

in producing alloys

For human purposes, the actinides are particularly useful

as sources of radioactivity

In electron shielding, inner shell electrons partially shield valence electrons from the effects of

nuclear charge

The outer electron configuration of an element is ns²ns^5. To what group does this element belong?

7A

In Bohr's model of the atom, where are the electrons and protons located?

The electrons move around the protons, which are at the center of the atom.

What is the maximum number of electrons in the third principal energy level?

18

The shape (not the size) of an electron cloud is determined by the electron's ____.

energy sublevel

If the spin of one electron in an orbital is clockwise, what is the spin of the other electron in that orbital?

counterclockwise

What types of atomic orbitals are in the second principal energy level

s and p

What is the next atomic orbital in the series 1s, 2s, 2p, 3s, 3p?

4s

Define the Aufbau Principle

Electrons fill atomic orbitals in order of increasing energy, from the lowest energy level to the highest

Define the Pauli Exclusion Principle

no two electrons in the same atom can have the same four quantum numbers

In the Bohr model of the atom, an electron in an orbit has a fixed ____.

energy

Define Hund's Rule

electrons will fill orbitals of equal energy (degenerate) singly with parallel spins before they start pairing up.

If three electrons are available to fill three empty 2p atomic orbitals, how will the electrons be distributed in the three orbitals?

one electron in each orbital

How many half-filled orbitals are in a bromine atom?

1

The most stable electron configurations are likely to contain

filled energy sublevels

How does the speed of visible light compare with the speed of radio waves, when both speeds are measured in a vacuum?

the speeds are the same

Which color of visible light has the shortest wavelength?

violet

How does the energy of an electron change when the electron moves further from the nucleus?

it increases

How are the frequency and wavelength of light related?

they are inversely proportional to eachother

What is the wavelength of an electromagnetic wave that travels at 3.00 x 10^8 m/s and has a frequency of 60 MHz? (1 MHz = 1,000,000 Hz)

300,000,000 m/s/60,000,000 Hz

Emission of light from an atom occurs when an electron

drops from a higher to lower energy level

The atomic emission spectra of a helium atom on Earth and of a helium atom in the sun would be

the same

What is the approximate energy of a photon having a frequency of 4.10 x 10^7 Hz? (h = 6.626 x 10^-34 J•s)

2.72 x 10^-26 J

The principal quantum number indicates what property of an electron?

energy level

What is the shape of the 3p atomic orbital?

dumbbell

What is the maximum number of p orbitals in a principal energy level?

3

Define valence electrons

the electrons in the outermost shell of an atom

Which variable is directly proportional to frequency?

energy

What are quanta of light called?

photons

When an electron moves from a lower to a higher energy level, the electron

absorbs a quantum of energy

What is the number of electrons in the outermost energy level of an oxygen atom?

6

What is the electron configuration of potassium?

1s2 2s2 2p6 3s2 3p6 4s1

How many unpaired electrons are in a sulfur atom, which has the atomic number 16?

2

What is the basis for exceptions to the aufbau principle?

Filled and half-filled energy sublevels are more stable than partially-filled energy sublevels.

Which electron configuration is most stable

One with a full valence shell, and full subshells

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit

increase

How many energy sublevels are in the second principal energy level?

2

What is the maximum number of f orbitals in any single energy level in an atom?

7

What is the maximum number of orbitals in the p sublevel?

3

What is the approximate frequency of a photon having an energy 5.50 10^-24 J? (h = 6.626 10^-34 J•s)

8.30 x 10^9 Hz

How do the energy differences between the higher energy levels of an atom compare with the energy differences between the lower energy levels of the atom?

they are smaller in magnitude than those between lower energy levels

Bohr's model could only explain the spectra of which type of atoms?

single atoms with one electron

The quantum mechanical model of the atom

involves the probability of finding an electron in a certain position