Aleksza/Soltis
Chemistry
2012-13
TED-Ed –Describing the invisible properties of gas by Brian Bennett
http://ed.ted.com/lessons/describing-the-invisible-properties-of-gas-brian-bennett#review
_____1. Why can’t we observe gases with our eyes?
A.
B.
C.
D.
Gases move too quickly
Gases are too small to see
Gases are invisible, even to microscopes
Gases only exist for short bursts of time.
2. If gases have very high kinetic energy (in other words, they move around very fast),
how do you think liquid molecules behave? What about solids?
_____3. What is a scientific model?
A.
B.
C.
D.
A person that models lab coats and lab equipment for catalogs
An explanation of why something works the way it does.
An attempt to describe an observed phenomenon.
The same thing as a scientific law, like the Law of Gravity.
4. If you were given oxygen (MM = 18amu) and hydrogen (MM = 1 amu) at the same
temperature and pressure, which has more energy? Which gas would be moving
faster? Why? How is this different than energy?
_____5. Why do individual gases have a volume of zero?
A.
B.
C.
D.
They are nearly single atoms, so their volume is negligible
It makes it easier for us to describe their behavior
Gases don’t make a difference unless they have a volume of zero
Gases are so large, we don’t try to measure the volume
_____6. Which of the following explains how energy remains constant in a collision.
A. Gas particles don’t ever actually collide, so the energy doesn’t change, keeping it
constant
B. The large particles move faster than the small particles, so the energy isn’t changing.
C. When gases collide, no energy transfers from one to the other
D. In collisions, large particles give energy to smaller particles, keeping the total constant.
_____7. How is temperature related to gas activity?
A.
B.
C.
D.
The cooler the temperature, the faster the gases move
Smaller gases have more energy that larger gases at the same temperature
As the temperature increase, the gas particles slow down at the same rate
All gases have the same energy at the same temperature
HOMEWORK BONUS (5 points): Most hot air balloons are round. Yes, you can have
some other shapes but its shape is still rounded. Using the assumptions, explain why a
square hot air balloon would be hard to make.