What is a valence electron?

• The sum of neutrons and protons.
• The # of electrons in the last shell.
• A type of bond.
• A popular compound.

Ionic bonds are between...

• nonmetals and nonmetals
• carbon and oxygen
• metals and nonmentals
• hydrogen and chlorine

Covalent bonds are between...

• two or more nonmetals
• sodium and chlorine
• metals and metals
• metals and nonmetals

sulfuric acid

• HSO₃

• H₂SO₃

• H₂SO₄

• H₃SO₄

Mg(OH)₂

• magnesium hydroxide acid
• hydromagnesium acid
• magnesium oxygen hydride
• magnesium hydroxide

In a neutralization reaction, what are the products of a reaction between an acid and a base?

• Another acid and base
• Carbon dioxide and a salt
• Water and a salt
• Either two acids or two bases

Basic oxide

• BaO

• P₂O₅

• ZnO

• CO₂

How are metal oxides formed?

• When metals react with oxide.
• When metals react with water.
• When metals react with air.
• When metals react with oxygen.

Which is NOT an amphoteric oxide?

• zinc oxide

• aluminium oxide

• lead (II) oxid

• sodium oxide

Which of the followings is an acidic oxide?

• SO₂

• H₂O

• CO

• ZnO