Day 3 - 8th Grade Science STAAR Review THMS

Felipe is observing how acetic acid (vinegar) and sodium bicarbonate (baking soda) react with one another in a volcano model. What evidence can Felipe look for to indicate a chemical reaction has taken place? 

• The volume of the acetic acid increases. 
• The density of the baking soda decreases. 
• Gas bubbles are produced.
  
• The baking soda is dissolved. 

Tags

NGSS.MS-PS1-2

During a science lab, Jessica records the following data when Liquid A (clear) and Liquid B (clear) are combined in a beaker:
 
Did a chemical change occur? Why? 

• Yes, a new yellow liquid is formed 
• Yes, mixing any two unknown liquids will cause a chemical change 
• No, there was no change in temperature
  
• No, there was no change in the state of matter 

Tags

NGSS.MS-PS1-2

A science class is placing an iron rod outside and another inside a sealed plastic container. Several weeks later, the iron rod outside has rusted. What research question was the class attempting to answer? 

• Will a physical change occur on either iron rod? 
• How often do iron rods rust? 
• Will the iron rod inside gain mass when compared to the iron rod outside? 
• Will there be a difference in the speed of the chemical change between the two iron rods? 

Tags

NGSS.MS-PS1-2

Which of the following pictures is an example of a chemical change? 

• Wood burning in a fireplace
• ice melting in water in a beaker
• a cracked rock
• boiling water on a hotplate

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Marlene’s family goes on an autumn campout to a local state park. During her campout she notices several things that could be chemical changes. Which of the following is not considered a chemical change? 

• leaves on the trees turning from green to red 
• the campfire turning wood into ashes
  
• the clouds forming rain from water vapor 
• a marshmallow turning black on the outside when cooked over the campfire 

Tags

NGSS.MS-PS1-2

Which statement is most likely true in explaining the difference in these two pennies? 

• The penny on the left has collected dirt on its surface. 
• The penny on the right is not made of copper. 
• Each penny was minted in a different location using different metal alloys. 
• The penny on the left has undergone a chemical change on its surface. 

Tags

NGSS.MS-PS1-2

Susan observes two antacid tablets dropped into water. Bubbles immediately form. When will she know the chemical reaction has stopped? 

• when the bubbles have completely disappeared
  
• when the temperature of the water begins to decrease 
• when a white substance begins to form at the bottom 
• when heat is produced from the water 

Tags

NGSS.MS-PS1-2

Which of the following pieces of lab equipment is needed to measure the amount heat energy released during a chemical change? 

• A
• B
• C
• D

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-3

 Which of the following chemical equations for a reaction between carbon dioxide and water is considered balanced? 

• 3CO₂ + 6H₂O --> C₆H₁₂O₆ + 3O₂ 
• 6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂ 
• 3CO₂ + 2H₂O --> C₆H₁₂O₆ + 6O₂ 
• CO₂ +H₂O --> C₆H₁₂O₆ +O₂ 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In question #9, what is the mass of the products compared to the mass of the reactants? 

• The mass of the products is equal to the mass of the reactants. 
• The mass of the products of the chemical reaction is always greater than the reactants. 
• Some of the mass is lost in the reaction, so the mass of the reactants is greater. 
• There is not enough information. It depends on the conditions of the reaction. 

Tags

NGSS.MS-PS1-5