Chemical Formulas Quiz

What does a chemical formula show?

• The elements in the compound and the ratio of their atoms

• The color of the compound

• The taste of the compound

• The temperature at which the compound melts

In the chemical formula H₂O, how many hydrogen atoms are present?

• 2

• 1

• 3

• 4

In the chemical formula H₂O, how many oxygen atoms are present?

• 1

• 2

• 3

• 4

What is a molecule?

• A single atom

• A group of two or more atoms held together by chemical bonds

• A substance made of one type of element

• A mixture of different substances

What distinguishes a compound from a molecule?

• Compounds are made of only one type of atom

• Compounds are substances formed by two or more different types of elements chemically combined in a fixed proportion

• Molecules are always larger than compounds

• Molecules are substances formed by different types of elements

Why is oxygen gas (O2) not considered a compound?

• It is not made of atoms

• It is made of only one type of element

• It is not held together by chemical bonds

• It is a mixture of different elements

What is a chemical bond?

• A weak force between molecules

• A strong attractive force between atoms or ions in a molecule or compound

• A type of chemical reaction

• A process of breaking down compounds

How can a chemical bond be formed?

• By heating the atoms

• By transferring or sharing electrons

• By mixing different compounds

• By cooling the molecules

What is the main reason behind bond formation?

• Color

• Stability

• Size

• Shape

Which of the following is a way elements can become stable?

​ (a)   ​ (b)   ​ (c)  

• Gain electrons
• Lose electrons
• Share electrons
• change color
• nuclear blast exploding electrons to correct order