Classification of Matter
Formative Assessment No. 2
Instructions
You may print this sheet, if you wish, but it is not
necessary. Please show work carefully and clearly put a box
around the final result of your calculation. This means
that every conversion factor must be shown and you must
show the units that cancel out. Scan your work and submit
it as a PDF. Problems are 10 points each. For completing
the assessment you earn a 70. The bonus question is worth 5
extra points and it is permitted to earn up to 105.
Two questions:
What is the difference between a substance and a mixture?
How is a compound different from a mixture?
Give an example of a homogeneous mixture. Give an example of a heterogeneous mixture. What makes these two types of mixtures different from one another?
Adding heat causes solids to melt. Here are two possible explanations for why this happens:
As heat is added the molecules get less sticky. The forces that make the molecules stick together get weaker and they can’t hold the particles together anymore.
As heat is added the molecules move around at higher speeds but the forces between them have the same strength as before. Becuase of this they have enough energy to break the forces that hold them together when the material is a solid.
Which of these two explanations is correct? Explain why.
Bonus: What is the difference between a chemical change and a physical change when you describe these based on the behavior of particles?
Did you do your own original work here? If not then you will not be able to receive feedback that is tailored to your specific learning needs. Remember, you earn a 70 just for trying all the problems. I give partial credit for attempts that show some level of skill. The point of this assignment is for you to test yourself. It is not to get a good grade. If you work hard, ask questions, and get help when you need it the grade will take care of itself. Please concern yourself with learning.