6th Grade Science LMS Semester Review 2

What is the product ( after the reaction) of the chemical reaction?  2Ca+ O₂ → 2CaO

• metal
• mixture
• solution
• compound

Which of the following is an example of a compound?

• copper
• iron
• carbon
• water

Which of these is an element?

• KBr
• O₂
• 2KCl
• FeO₂

Which demonstrates a chemical change?

• glass breaking
• a garbage can rusting
• sugar dissolving in water
• water evaporating from a sidewalk

  Louis was investigating physical and chemical changes in matter. Which of these changes that Louis found involves a chemical change in matter?

• evaporation of water
• grinding of rock
• melting of ice
• rusting of iron

This equation expresses which change? 
Mg + S → MgS

• 2 atoms combine to form one atom
• two atoms combine to form one molecule
• Two elements combine to form a different element
• two elements combine to form two new elements

Physical and chemical properties can be used to classify substances. Which of these shows a chemical property?

• Silver melts
• Magnesium burns
• sulfur is a yellow solid
• Aluminum conducts heat

A student mixed some yellow sulfur powder with some iron filings. She was able to take the iron out of the sulfur by using a magnet. She then remixed the iron and sulfur in a test tube and heated it. After it cooled, she removed the substance from the test tube but could not separate the iron from the sulfur using the magnet. Which type of change occurred in the material when it was heated?

• a physical change because the iron reacted with the sulfur
• a chemical change because a new substance was formed
• a physical change because a compound was formed
• a chemical change because a magnet had to be used

A student kept her bicycle outdoors. After a few seasons, some of the metal on the bicycle became reddish-brown and flaky.
What happened to the metal on the bicycle?

• The metal was damaged by insects
• The metal became covered with pollution
• The metal was used over time and became worn out
• The metal combined with water and formed a new substance

Mrs. Garza’s class mixed some materials. They made a table of the materials and the products after the materials combined.
Based on the table, which materials mixed to form a new substance?

• water and flour
• water and salt
• iodine and flour
• iodine and salt