Electrons and the Periodic Table

How many valence electrons are found in atoms of group 15?

• 4
• 5
• 2
• 3

Tags

NGSS.HS-PS1-1

What are valence electrons?

• The total number of electrons in an atom

• The number of electrons in the outermost shell

• The number of electrons in the second shell

• The number of protons in the outermost shell

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Potassium ion

• Na⁺
• K⁺
• K²⁺
• K⁻

Look at the periodic table. What should be the charge on the ion formed by calcium?

• +1

• +2

• -1

• -2

Tags

NGSS.HS-PS1-1

Anions have

• gained electrons.

• lost electrons.

• gained protons.

• lost protons.

What is an anion?

• A negatively charged ion

• An atom with no charge

• A positively charged ion

• A stable atom found on the periodic table

If an atom loses electrons, the charge will be positive.

• true

• false

Tags

NGSS.HS-PS1-7

Most elements are most stable when their outermost energy levels contain ________ electrons.

• 2

• 6

• 8

• 18

Tags

NGSS.HS-PS1-1

What are the elements in group 17 of the periodic table called?

• Alkali metals

• Alkaline earth metals

• Halogens

• Noble gases

What are the elements found along the "staircase" called? They have properties of both metals and non-metals.

• Metalloids

• Non-metals

• Transition metals

• Metals