Checkpoint Chemistry

Second shell can hold up to

• 2 electrons

• 8 electrons

• 18 electrons

• 32 electrons

The horizontal lines in the modern periodic table are called

• Family

• Group

• Period

• Atomic number

All the elements in a group in the periodic table have the same

• Same number of valence electrons

• Atomic number

• Atomic weight

• Same number of shells

Elements are arranged in order of

• Decreasing atomic number

• Decreasing atomic mass

• Increasing atomic number

• Increasing atomic mass

How many electrons are there in the third shell (principal energy level) of the atom with atomic number 23?

• 2

• 5

• 8

• 18

Which chemical equation shows a displacement reaction?

• Carbon + oxygen → carbon dioxide

• Copper sulfate + magnesium → magnesium sulfate + copper

• Magnesium + oxygen → magnesium oxide

• Sodium hydroxide + hydrochloric acid → sodium chloride + water

Which chemical equation shows a neutralization reaction?

• Carbon + oxygen → carbon dioxide

• Copper sulfate + magnesium → magnesium sulfate + copper

• Magnesium + oxygen → magnesium oxide

• Sodium hydroxide + hydrochloric acid → sodium chloride + water

Which chemical equation shows the formation of a metal oxide?

• Carbon + oxygen → carbon dioxide

• Copper sulfate + magnesium → magnesium sulfate + copper

• Magnesium + oxygen → magnesium oxide

• Sodium hydroxide + hydrochloric acid → sodium chloride + water

Which is an ionic compound?

• CuSO₄

• C₂H₆

• CO₂

• H₂O

What is the correct chemical formula of copper (II) sulfate penta hydrate.

• Cu₂SO₄.5H₂O

• Cu₂(SO₄)₂.5H₂O

• 5 Cu₂SO₄. H₂O

• CuSO₄.5H₂O