Newton's Laws
What do all three of Newton's laws describe?
Motion
What do I have if I have a substance with only one type of molecule or atom?
A pure substance
Where is most of the mass of an atom?
Nucleus, because protons and neutrons have a much greater mass than electrons
Velocity is speed in a given...
Direction
What is a characteristic property? Give one example.
A property that stays the same even when the sample size changes: Examples:
1. Boiling point
2. Freezing point
3. Density
What is the formula for "force"?
Force = Mass X Acceleration
Density equals mass divided by volume
What is the smallest part of an element that has all of its characteristic properties?
Atom
What is a force?
A push or a pull
What is volume?
The amount of space that an object takes up
A figure skater is going at a constant velocity. Then he lifts his partner (increasing his mass). What happens to his acceleration?
Acceleration decreases because mass increases and force stays the same.
Give one characteristic of a physical change.
1. Change in size
2. Change in shape
3. Change in phase
Protons and neutrons are both part of an...
atom
Name one factor that affects gravity.
1. mass
2. distance
What part of an atom is involved in chemical bonding?
Electrons
What two factors affect acceleration?
Force and mass
Give one characteristic of a chemical change.
1. Producing a gas
2. Producing a precipitate
3. Change in temperature
4. Change in color/taste/smell
What is one difference between protons and electrons?
1. Protons are inside the nucleus. Electrons are outside the nucleus.
2. Protons have much greater mass.
If two opposing forces are pushing on a block and the forces are the same number of newtons, what will happen to the block?
It will stay still
If I have two substances that are not chemically bonded, what do I have?
A mixture
If forces on an object are balanced, what will happen to the object?
The object will not move
Name one thing that happens to the molecules in a substance when thermal energy is added?
1. They move more quickly
2. They move farther apart
3. They have weaker bonds
What is a molecule made up of?
Two or more atoms that are bonded together
If two opposing forces are pushing on a block and one is pushing north at 10 newtons and one is pushing south at 5 newtons, what is the net force?
North 5 newtons
What is the difference between a chemical reaction and physical change?
A chemical reaction creates a new substance.
In a physical change, the substance stays the same. Just the size, shape, or phase changes.