Show:
Motion
Forces
Structure of Matter
Periodic Table
Grab Bag
100
What is velocity?
Speed and direction
100
The net force on an object is 0 Newtons. What do you know about the forces acting on the object?
The forces are balanced. This means that the object will have NO CHANGE in motion - it just keeps doing what it was doing before.
100
Describe the structure of the atom.
Protons and neutrons are found in the center of the atom, called the nucleus. Electrons orbit around the outside of the nucleus.
100
How do you find the number of protons in an atom?
Use the periodic table! The atomic number (the whole number above the element symbol) is equal to the number of protons.
100
What is the equation for density?
Density = Mass/Volume (mass divided by volume)
200
What is the equation for speed?
distance = speed x time
200
True or False: If the forces acting on an object are balanced, we know the object is not moving (speed = 0).
FALSE! It's possible that the object is not moving, but it's also possible the object is moving at a constant (not changing) speed.
200
What is the charge and mass of protons, neutrons, and electrons?
Protons: positive charge; mass = 1 amu Neutrons: no charge, mass = 1 amu Electrons: negative charge, mass = 0 amu
200
How do you find the number of electrons in an atom?
The number of electrons is equal to the number of protons.
200
What is density?
Density is a ratio of mass to volume. Density compares the mass of an object (how much "stuff" makes up an object) to its volume (how much space it takes up).
300
When does velocity change?
Velocity changes when the speed of an object changes, the direction an object is moving changes, or both change together.
300
What does an unbalanced force tell you?
The velocity of the object is changing. That means either the speed of the object is changing or the direction the object is traveling is changing (or both!).
300
What determines the state of matter of a substance?
Remember, state of matter = solid, liquid, or gas. The motion of the particles that make up the substance determines the state of matter of a substance (which is determined by how much energy the particles have).
300
What are isotopes?
Isotopes are different versions of the same element. Isotopes have the SAME number of protons and a DIFFERENT number of neutrons.
300
What happens to melting point, density, and conductivity as you move to the right across the periodic table?
Melting point, density, and conductivity all DECREASE as you move to the right across the periodic table. Metals have a higher melting point, greater density, and greater conductivity than nonmetals.
400
How do you find the average speed of an object if it's speed changes over time? (For example: an object travels at 30 miles/hour for 10 minutes and then 50 miles/hour for 20 minutes).
Solve d=st using the TOTAL distance traveled by the object and the TOTAL amount of time the object was moving.
400
In which direction do friction and air resistance act on an object?
In the direction OPPOSITE of the direction the object is moving. If an object is falling down, air resistance acts up. If a ball is rolling to the right, friction acts to the left.
400
List the states of matter in order from MOST molecule motion to LEAST molecular motion.
Gas - Liquid - Solid
400
On the periodic table, where are elements similar to platinum (Pt) located?
Elements similar to platinum are in the same group as platinum, meaning they are in the same column. Therefore, look at the elements above and below platinum to find an element similar to platinum.
400
What does a flat line on a distance v. time graph tell you? What does a flat line on a speed v. time graph tell you?
A flat line on a distance v. time graph means the object is not moving (its distance is not changing and the slope is 0). A flat line on a speed v. time graph means the object is moving at a constant speed (for example, the object is moving at a constant speed of 2 miles/hour).
500
What does the slope of a distance v. time graph represent?
Speed
500
Is there ever a situation when there are no forces acting on an object?
Not on Earth! On Earth gravity ALWAYS pulls objects toward the center of the Earth.
500
How do the properties of a compound (example: NaCl) compare to the properties of its individual components (Na and Cl)?
The properties are DIFFERENT!
500
Name 4 macromolecules.
DNA, protein, fat, and carbohydrates.
500
Tell me about the inert gases. What are they, where are they located on the periodic table, and why are they special?
The inert gases are located in group 18 on the periodic table (the last column to the right). The inert gases are helium, neon, argon, krypton, xenon, and radon. The inert gases are special because they do not react with other elements.