Modern Periodic Table

What is the periodic trend for atomic radius as you move from left to right across a period?

• The atomic radius decreases

• The atomic radius fluctuates

• The atomic radius increases

• The atomic radius remains constant

How many groups are there in the modern periodic table?

• 12

• 20

• 25

• 18

What is the atomic number of carbon?

• 8

• 6

• 12

• 20

What is the atomic mass of oxygen?

• 12.011 u

• 14.007 u

• 15.999 u

• 16.999 u

How many valence electrons does an element in group 1 have?

• 0

• 8

• 2

• 1

What is the chemical property of halogens?

• High reactivity and electronegativity

• High boiling point and melting point

• No effect on other elements

• Low reactivity and electronegativity

What happens to the atomic radius as you move down a group?

• Increases

• Fluctuates

• Remains constant

• Decreases

What is the period number of the element with atomic number 19?

• 8

• 4

• 6

• 2

What is the relationship between atomic number and the number of protons in an atom?

• The atomic number is half the number of protons in an atom.

• The atomic number is equal to the number of protons in an atom.

• The atomic number is equal to the number of electrons in an atom.

• The atomic number is equal to the number of neutrons in an atom.

How many valence electrons does an element in group 17 have?

• 7

• 5

• 1

• 3