Unit 2 Review IPC

An atom of beryllium (Be) has 4 protons. It has a net charge of 0. How many electrons does it have?

• 4

• 2

• 1

An atom has an atomic number of 32. What is the chemical symbol for the atom? Use the periodic table.

• Eu

• Pb

• Ge

According to Bohr's model of the atom, in which orbitals do electrons have the most energy?

• innermost orbitals

• outermost orbitals

What may happen to the electron when it gains energy?

• It may move to a higher energy level.

• It may drop to a lower energy level.

Which model is Bohr credited with developing?

• the plum pudding model of the atom

• the orbital model of the atom

• the nuclear model of the atom

Which subshell can have a maximum of 2 electrons?

• f

• d

• p

• s

How many electrons would make the d shell complete? Use an aufbau diagram.

• 2

• 6

• 10

An electrically neutral atom has the electron configuration 1s2 2s2 2p6 3s2 3p4. What is the name of this atom? Use the periodic table.

• Phosphorous

• Chlorine

• Sulfur

What is the electron configuration for an electrically neutral atom of oxygen (O)? Use the periodic table.

• 1s2 2s2 2p4

• 1s2 2s2 2p6

• 1s2 2s2

What did Rutherford's gold-foil experiments prove the existence of?

• the protons

• the nucleus

• electrons outside the nucleus