Pure Substance and Mixtures

Compounds are pure substances made from two or more elements chemically combined. What is the name of the illustration that shows all the known elements?

• element table
• periodic table
• star chart
• solar system model

Water is a neutral compound.  Based on the pH scale, what is the pH of water?

• 0
• 7
• 10
• 14

A magnet was placed near a pile that contained both iron and sulfur. The magnet was moved gradually closer to the pile. As it neared the pile, the magnet started attracting small pieces of iron from the pile. 
Which of these statements best describes the contents of the pile?

• It is a heterogeneous mixture of iron and sulfur that can be separated by magnetism.
• It is a solution of iron and sulfur that can be separated by magnetism.
•  It is a compound of iron and sulfur that can be separated by magnetism.
• It is a suspension of sulfur in iron that can be separated by magnetism.

Of these mixtures, which one is a solution?

• A
• B
• C
• D

In this picture, which represents atoms?

• A
• B
• C

In this picture, how would you best label or describe A and B?

• products
• elements
• reactants
• producers

In this picture, which one represents a compound?

• A
• B
• C

Of these mixtures, which one is a suspension?

• A
• B
• C

Some compounds are classified as acids or bases. The pH scale shows how acidic or how basic these compounds are. The lower the pH, the more acidic a compound is. The higher the pH, the more basic it is. Sodium hydroxide, a compound commonly found in drain cleaners, has a pH of 13.

• highly basic
• highly acidic
• slightly basic
• slightly acidic

In this picture, which represents an element?

• A
• B
• C