7 th Grade Quarterly Assessment TWO

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 Question 1

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

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 Question 11

Use the information below to answer questions 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.

Which graphs show the trends in the mass (M) and temperature (T) changes during the baking soda and vinegar reaction shown in the diagram? Question 13

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 1- second 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)