8.6 Matter and Energy Review

Which of the following statements about elements and compounds is accurate?

• Elements are many different types of atoms together but compounds are just one type of atom.

• Elements are pure substances that cannot be broken down physically but compounds are pure substances that can be broken down physically.

• Elements are not found on the Periodic Table but compounds are found on the Periodic Table.

• Elements are pure substances that cannot be broken down chemically but compounds are pure substances that can be broken down chemically.

Which element is found in all organic compounds?

• Carbon (C)

• Nitrogen (N)

• Hydrogen (H)

• Oxygen (O)

The air that surrounds us is categorized as which of the following?

• Element

• Compound

• Mixture

• Organic compound

Which of the following could be the chemical formula for a compound?

• Na

• CO₂

• H₂ + O₂

• Au

Which of the following could be the chemical formula for an element?

• Si₂

• H₂O

• C + O₂

• C₆H₁₂O₆

Which of the following could be the chemical formula for a mixture?

• Ne
• CO₂

• H₂

• NACl + H₂O

How could you separate a mixture of sand and water?

• Pick out each sand grain

• Allow the water to evaporate

• Drink the water

• This mixture cannot be separated

Which of the following is not an example of an element?

• Platinum

• Zinc

• Glucose

• Helium

Which of the following provides the number of atoms of an element?

• Coefficient

• Chemical symbol

• Subscript

• Capitals

Which of the following provides the number of molecules of an element or compound?

• Coefficient

• Chemical symbol

• Subscript

• Capitals