7th Grade Quarterly Assessment
TWO
Question 1
In any physical or chemical
process, what two quantities are
always conserved?
A. matter and total energy
B. light and acoustic energy
C. density and thermal energy
D. gravity and potential energy
Use the power-plant diagrams and information below to answer questions 2-3
An electric power plant in Toledo, Ohio, is powered by coal (see Figure 1). The coal is
burned to boil water and produce steam. The steam turns a turbine, which causes the
generator to produce electricity.
The power plant in Belleville, West Virginia, is hydroelectric (see Figure 2). Water from the
lake behind the dam falls on the turbine blades. The turbine turns, which causes the
generator to produce electricity.
Question 2
Which describes a chemical change and a physical change that take place
during the
production of electricity in the coal-fired power plant (Figure 1)?
A. The coal moving along the conveyor belt is a chemical change.
The coal burning to give off heat and carbon dioxide gas is a physical change.
B. The coal burning to give off heat and carbon dioxide gas is a chemical
change. The boiling water turning to steam is a physical change.
C. The boiling water turning to steam is a chemical change. The steam turning
the turbine is a physical change.
D. The steam turning the turbine is a chemical change. The turbine running
the generator to produce electricity is a physical change
Question 3
The hydroelectric plant (Figure 2) uses a renewable energy resource. Which statement
describes why this resource is considered renewable?
A. Heated water turns the turbine. The used water flows upstream
back directly into the lake and may be used again right away.
B. Falling water turns the turbine. The used water flows
upstream back directly into the lake and may be used again
right away.
C. Heated water turns the turbine. The water is returned to
the river downstream, so it may continue in the water cycle.
D. Falling water turns the turbine. The water is returned to the
river downstream, so it may continue in the water cycle.
Use the information below to answer questions 4-5.
Motion Diagram
The graph below shows the position of a car in motion along an east-west
road over a period of 10 minutes. The car’s position is recorded at 1-minute
intervals. At time = 0, the car’s position is at the starting point.
Question 4
What is the car’s motion relative to the starting
point at time = 8 minutes?
A. at rest at the starting point
B. in motion at the starting point
C. moving toward the starting point
D. moving away from the starting point
Question 5
What is the total distance traveled by the car
after 10 minutes?
A. 600 meters
B. 1,200 meters
C. 2,000 meters
D. 3,600 meters
Use the information in the table below to answer questions 6-8.
Properties of Some Substances
A scientist measures out 15 mL each of baking soda, salt, sugar, iron filings, and corn
starch. She runs a series of procedures and records her results in the table below. The
first column in the table indicates the procedure. The remaining columns indicate her
results for each substance.
Question 6
According to the information in the table, what
comparison can the scientist make about the
densities of sugar and corn starch?
A. Sugar is more dense than corn starch.
B. Corn starch is more dense than sugar.
C. Sugar and corn starch have the same density.
D. Both sugar and cornstarch are more dense
than salt.
Question 7
What two changes does sugar undergo when
heated in a spoon over a flame?
A. two physical changes
B. two chemical changes
C. a chemical change and then a physical change
D. a physical change and then a chemical change
Question 8
The scientist observes the rust on the sample of
iron filings and dries the sample thoroughly. The
scientist weighs the entire sample and finds that it
has more mass than the original 118 grams. What
explains this increase in mass?
A. The sample gained mass during drying.
B. The sample gained mass during a physical
change.
C. The sample gained mass during a change of state.
D. The sample gained mass during a chemical
change.
Question 9
A tightly sealed glass box has amass of 20,000 grams and contains a 5-gram cube of
ice, making the total mass 20,005 grams. The box with the ice is placed in direct
sunlight. After three hours, the box appears to be empty, with just small droplets
along the sides of the box. Which statement describes the mass of the sealed box
after sitting in the sun?
A. The mass decreases because the ice melted into a liquid.
B. The mass remains the same as the ice melts and then evaporates.
C. The mass increases as the gases inside the box absorb energy and expand.
D. The mass increases as the water vapor condenses into small droplets on the glass.
Question 10
Electricity is produced in a hydroelectric plant
when moving water turns a turbine. Which
describes this energy transformation from the
turning turbine to electricity?
A. kinetic energy into electric energy
B. nuclear energy into electric energy
C. thermal energy into electric energy
D. chemical energy into electric energy
Question 11
A ball is released from rest at position 1. The diagram shows the ball in four
positions as it rolls along a track from left to right.
In which position does the ball have its minimum gravitational potential energy
and maximum kinetic energy?
A. 1
B. 2
C. 3
D. 4
Use the information below to answer questions 12-13
Baking Soda and Vinegar Reaction
Students perform a chemistry experiment by mixing baking soda with vinegar. They
mix 4 grams of baking soda with 50 grams of vinegar in a 6-gram plastic cup as shown
below. The cup is left uncovered. The students record the mass and temperature of
the mixture every 5 seconds. They continue these observations until 10 seconds after
they see the mixture stop bubbling. Their data are shown in the table below.
Question 12
The data in the table show the temperature of the cup-baking soda-vinegar system.
The temperature of the surrounding air was not measured. Assuming that the total
amount of energy remains constant, what conclusion about energy transfer does the
temperature data support?
A. Thermal energy was lost from the surrounding air and the system.
B. Thermal energy was gained by the system and the surrounding air.
C. Thermal energy was transferred from the surrounding air to the system.
D. Thermal energy was transferred from the system to the surrounding air.
Question 13
Which graphs show the trends in the mass (M)
and temperature (T) changes during the baking
soda and vinegar reaction shown in the diagram?
Use the information below to answer questions 14 and 15.
Block and Ramp
Students investigated the motion of wooden blocks on ramps. They used two boards,
each two meters long, to create ramps. They set the ramps up at different heights, as
shown in the diagram below. Next they took two identical blocks (I and II) and placed
one at the top of each ramp. They placed the blocks so that the back edge of each
block was even with the edge of the ramp (distance = 0 meters). The students held the
blocks so that the blocks would not slide until the students released them. The students released
the blocks at time = 0 seconds. They measured the total distance traveled by each block at 1second intervals as the blocks slid down the ramps. The students recorded their results as shown
below.
Question 14
Which conclusion is supported by the results of this investigation as
expressed in the data table?
A. As the travel time increases, the speed of the block decreases.
B. As the ramp steepness is increased, the travel time of the block increases.
C. As the distance traveled increases, the average speed of the block increases.
D. As the height of the ramp is increased, the average speed of the block decreases.
Question 15 - Extended response.
In your Answer, name two forces that acted on
the blocks as they slid down the ramps.
Describe or show how each force you listed
affected the motion of the block. (4 points)