Chemical Reactions

For an investigation a student poured a blue solution of CuSO₄ into a beaker. The student placed a shiny, silver-colored strip of zinc metal in the solution and observed the changes.
The student inferred that a chemical reaction occurred. What evidence supports this inference?

• A dark solid formed on the zinc metal.
• 
  The zinc metal remained silver-colored and shiny
• The CuSO₄ solution turned blue when the zinc metal was added.
• None of these

Tags

NGSS.MS-PS1-2

Which of the following is an example that includes evidence of a chemical reaction?

• A sample of zinc is placed in water and it settles to the bottom
• A solid block of ice is heated and it completely melts into a liquid. 
• Sugar that is burned gives off an odor and turns brown and then black.
• A tomato is placed into a blender and chopped up into smaller pieces.

Tags

NGSS.MS-PS1-2

The smell made from a decomposing fish.

• Chemical Change
• Physical Change

Tags

NGSS.MS-PS1-2

Which problem is balanced?

• PbO2 + 2H2  -->  PbO2 +H
• SO2 + H20 --> H + 2SO4
• 2Na + 2H2O --> 2NaOH2 + H2
• Fe + O2 -->  Fe2O3

Which of the following could indicate a chemical change? 

• All of the answers could indicate Chemical Change 
• a color change has occurred 
• bubbles appear 
• identifying one or more new chemical products 

Tags

NGSS.MS-PS1-2

Which of the following is a PHYSICAL change?

• Getting a haircut
• Rusty metal
• sour milk
• A compound

Which of the following IS a chemical change

• using chalk
• water freezing
• slicing cheese
• digestion

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is the law of conservation of mass?

• Matter changes when reacted or changed.
• The mass of all reactants are changed during a physical or chemical change
• The mass of the reactants is the same as the mass of the products
• The mass of the products is different than the mass of the reactants.

Tags

NGSS.MS-PS1-5

How many elements are in C₆H₁₂O₆?

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-1

How many Al atoms are in this compound?         4Al₂O₃

• 2
• 8
• 6
• 4

Tags

NGSS.MS-PS1-1