Elements, Compounds, and Mixtures Review

Which of the following statements is true?

• Elements are many different types of atoms together but compounds are just one type of atom.
• Elements are made of many different types of compounds.
• Compounds are arranged on the Periodic Table, but elements are not.
• Elements are made of just one type of atom, but compounds are two or more different types of atoms chemically bonded

Carbon, hydrogen, and oxygen can bond together to form sugar. Sugar has properties that are different from the elements it is made of. Therefore, sugar is a(n)

• element
• compound
• mixture

Carbon (C) and oxygen (O) are pure substances. Each is made of only one type of atom, but carbon atoms are different from oxygen atoms. Carbon and oxygen chemically combine to form carbon dioxide (CO2). Which of the following statements is true?

• carbon dioxide is an element and carbon and oxygen are compounds.
• carbon, oxygen and carbon dioxide are all compounds.
• carbon, oxygen and carbon dioxide are all elements.
• carbon and oxygen are elements and carbon dioxide is a compound.

What is the minimum (smallest) number of elements necessary to create a compound?

• 1
• 2
• 3
• 5

What is the most logical way to separate a mixture of sand and water?

• Pick out each sand grain
• strain through filter paper
• Drink the water
• This mixture cannot be separated

Compounds can be separated only by

• physically breaking the substance into smaller pieces
• chemically breaking the bonds between the atoms
• politely asking them to separate from each other
• filtering out the larger atoms from the smaller ones using a strainer

What is the smallest unit of an element called?

• atom
• molecule
• compound
• mixture

What do we call the smallest unit of a compound that keeps the same chemical properties as the compound?

• atom
• element
• molecule
• mixture

A mixture of two or more substances where one substance has dissolved the other. The substance appears clear because the particles are so small and cannot be separated by filtration. An example would be saltwater or mouthwash.

• solution
• suspension
• colloid

A mixture in which some of the larger particles settle out of the mixture after it has been standing or could be easily filtered out. An example would be muddy water or Italian salad dressing.

• solution
• suspension
• colloid