Science review 1
Which type of energy is stored.
Potential
Give an example of a chemical change (reaction)
Random Answers that may include: Burning stuff, changing the molecules permanently
Give an example of a physical change
Random answers that may include: bending, cutting, or melting something, but not changing the molcules in a permanent way.
the force that pulls objects toward one another
Gravity
the use of force to move an object a distance
Work
2 or more forces acting together on an object
Net Force
an objects speed in a particular direction
Velocity
a measure of the distance an object moves in an amount of time
Speed
A push or pull that causes an object to move, stop, or change direction
Force
a force between surfaces that causes them to resist motion
Friction
What does the Law of Conservation of Mass say?
Matter is never created or destroyed, but transformed into a different form.
What is the formula for finding density?
mass divided by volume
What is the process by which plants make energy from the sun?
photosynthesis
a change in speed or direction
acceleration
equal forces acting on a object in opposite directions
Balanced Force
What is the process by which dry ice transforms from a solid to a gas without going through the liquid phase?
sublimation
Which of these is a mixture?
A. carbon dioxide
B. water
C. salt water
D. sugar
C. salt water
What type of graph would you use to plot continuous data (ex. time vs temperature)
a. bar graph
b. line graph
c. pie chart
d. none of the above
b. line graph
Where do all living things on the earth originally get their energy from?
The sun
forces acting on an object that is unequal in size, and opposite in direction
Unbalanced Forces
What is evaporation?
a . gas turns to liquid
b. solid turns to liquid
c. liquid turns to gas
d. water turns to ice
c. liquid turns to gas
Which has more energy: a 50 kg rock or a 100 kg rock?
100 kg rock because more mass=more energy!
Frank has a beaker with a mixture of salt and water. He would like to recover the salt from the water. Which would be the best method to accomplish this?
a. evaporation b. reflection
c. freezing d. refraction
a. evaporation
Which of Newtons law is this.. " Law of inertia" an object at rest will stay at rest and an object in motion will stay in motion until a force acts upon it.
Newtons 1st Law
which law is - " Law of acceleration" The greater the force, the greater the acceleration
2nd
Characteristics of a substance that can be observed
Physical Properties
What are the some evidences of a chemical change?
Odor
Color
Precipitate
Gas
Temperature change (sometimes light and sound)
Tommy placed a black, white, silver, and blue can under a heat lamp with a thermometer in each one. Which one of the cans will be the coolest?
a. black, because it absorbs the heat
b. blue, because it wasn't under direct light
c. white because it would reflect light
d. silver, because it is shiny
c. white, because it would reflect light
combination of substances that cannot be easily seperated
solution
object 1= 15 g object 2= 30 g
Which object must you apply more force to in order to move it?
object 2
F=m x a
the ability of a substance to dissolve
solubility
Which is an example of a chemical change?
a. melting ice
b. dissolving salt in water
c. hammering metal into a thin sheet of foil
d. burning a piece of paper
d. burning a piece of paper
has a definite shape and volume
solid
What is the energy of motion called?
Kinetic energy
has definite volume but no definite shape
Liquid
Has no definite shape or volume
Gas
Changes a substance from a liquid to a solid
Freezing
Which Law states.. For every action,there is an equal and opposite reaction.
3rd law
Process by which a liquid changes into a gas
Evaporation
change in matter that does not affect chemical composition ( no new substance formed)
Physical Change
an objects resistance to a change in motion; the greater the mass of an object the more of this it has
Inertia
The starting substance in a chemical reaction
Reactant
A student wanted to look at pond water to see what organisms they could find. Which of the following tools would the student use?
a. balance b. graduate cylinder
c. microscope d. magnifying glass
c. microscope
A vehicle traveled 30 meters in 6 seconds. Calculate its speed.
5 m/s
process that changes substances into new substances ( substance can never change back)
Chemical Change
the new substance of the reaction
Product
the chemical property of being able to burn
Combustibility
In which situation is a chemical reaction not taking place
a. salt dissolving in water
b. rusting of an old car in a junk yard
c. burning gasoline in a car
d. digestion of food in our body
a. salt dissolving in water
The motion of atoms and molecules that creates a change in temperature
Thermal Energy
the flow of heat through a liquid or gas, causing hot parts to rise and cooler parts to sink
Convection
the passing of heat through a material while the material itself stays in place
Conduction
the transfer of heat through electromagnetic rays
Radiation
a material that reduces or prevents heat from passing through
Insulator
a material that allows heat to pass through it while the material itself stays in place
Conductor
Which is the best example of a chemical change?
a. fireworks exploding
b. cutting paper
c. crushing a can
d. melting snow
a. fireworks exploding
Process by which a gas changes into a liquid
Condensation
Bob wants to determine at what ramp height will a cart roll the fastest. What would be his independent variable?
a. speed of the cart
b. ramp length
c. ramp height
d. none of the above
c. ramp height
a wave that travels at the speed of light through space due to radiation
Electromagnetic Waves
objects ____ as they are heated
Expand
the combination of metal and other substances
Ore
a mixture between a liquid and particles of a solid. In this case the particles do not dissolve. Particles are suspended in the liquid.
Suspension
a measure of the pull of gravity on an object
Weight
dyes which measure the strengths of acids and bases
Indicators
objects _____ as they are cooled
Contract