Period 7: Chemistry Regents CW Review for our Exam 4!

What is the number of neutrons in an atom of Li-7

• 3

• 4

• 5

• 7

What is the net charge of an ion that has 10 protons, 9 neutrons, and 7 electrons?

• 1+

• 3+

• 1-

• 3-

The bright-line spectrum of an element in the gaseous phase is produced as

• protons move from lower energy states to higher energy states

• protons move from higher energy states to lower energy states

• electrons move from lower energy states to higher energy states

• electrons move from higher energy states to lower energy states

Tags

NGSS.MS-PS4-1

Which statement explains why Group 18 elements are stable and unreactive?

• They are all gases

• They have low melting points.

• Their valence electron shell has reached a full octet.

• They have high ionization energies

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

An atom of an element forms a +3 ion. In which group on the periodic table could this element be located?

• 1

• 2

• 13

• 17

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

When an atom of lithium loses an electron, the atom becomes a

• negative ion with a radius smaller than the radius of the atom

• negative ion with a radius larger than the radius of the atom

• positive ion with a radius smaller than the radius of the atom

• positive ion with a radius larger than the radius of the atom

Tags

NGSS.HS-PS1-2

Which element has chemical properties that are most similar to the chemical properties of fluorine?

• Boron

• Chlorine

• Neon

• Oxygen

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which element requires the least amount of energy to remove the most loosely held electron from a gaseous atom in the ground state?

• bromine

• calcium

• lithium

• silver

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which electron configuration represents a sulfur atom in an excited state?

• 2-8-6

• 2-7-7

• 2-8-8

Tags

NGSS.HS-PS1-1

What must occur when an electron in an atom returns from a higher energy state to a lower energy state?

• A specific amount of energy is released.

• A specific amount of energy is absorbed.

• The atom undergoes transmutation

• The atom spontaneously decays.

Tags

NGSS.HS-PS1-4