Chemistry Reference
In-Depth Information
“massing” an object is improperly called “weighing” an object. Mass and
weight are actually two different things. The mass of an object has nothing
to do with where it is located. If you measured the mass of a brick in your
chemistry lab and found it to be 1.89 kg, then it would have the same mass
if you sent it into space or transported it to the moon. The number of at-
oms that the brick contains wouldn't change just because you moved it
around, but its weight would change.
What we call weight is actually a measurement of the attraction be-
tween two objects, due to the force of gravity. If you weigh yourself in your
bathroom, you are measuring the force of gravitational attraction between
you and the Earth. If you weighed yourself on the moon, you would be
measuring the force of gravitational attraction between you and the moon.
It makes sense that your weight should change, due to where you actually
do the weighing, but your mass doesn't change due to a change in location.
Does this mean that your mass never changes? Your mass is a measure
of the amount of matter, or atoms, that you contain. As you eat, you take in
atoms, changing your mass. In fact, as you breathe, you take in atoms, slightly
changing your mass. Your mass does change, but it doesn't change based
on location. A brick, which doesn't eat or breathe, will maintain a constant
mass, unless it gets damaged.
Now, try the following practice questions and check your answers at
the end of the chapter before moving on to the next lesson.
Lesson 2-2 Review
1.
The _______________ of an object is the amount of space that it
takes up.
2.
The _______________ of an object is the amount of matter it
contains.
3.
We find the mass of an object with an instrument called a(n)
_______________.
4.
There are _____ cm
3
in one liter.
5.
Convert 3.43 dm
3
to cm
3
.
6.
Convert 563 ml to L.
7.
How many cubic centimeters does 4.3 liters represent?
8.
The volume of a liquid can be measured in a _______________
cylinder.
