Worksheets2025 STAAR Prep 8th Science
Total questions: 38
Worksheet time: 24mins
The equation for photosynthesis is shown.
Which statement about the equation BEST identifies evidence that mass is conserved during photosynthesis?
The number of molecules in the reactants is equal to the number of molecules in the products.
The number of molecules in the reactants is equal to the number of carbon atoms in the products.
The number of the states of matter in the reactants is equal to the number of states of matter in the products.
The number of atoms for each element in the reactants is equal to the number of atoms for each element in the products.
Which statement BEST describes a component of cell theory?
All cells from from molecules.
All cells come from pre-existing cells.
All cells create genetically identical cells.
All cells reproduce from simpler cells.
Which statement correctly describes one of the two gases?
The chemical formula for gas X is NO & is made of nitrogen & oxygen
The chemical formula for gas Y is N2O & is made of nitrogen & oxygen
The chemical formula for gas X is N2O2 & is made of neon & osmium
The chemical formula for gas Y is N3O3 & is made of neon & osmium
Using the table shown, which table column of information would BEST be used for knowing the chemical formula of NO2 ?
Number of atoms per molecule
Types of elements
Volume of sample
Molecular composition
Students measure the mass of two different substances in Test Tubes A and B. Both substances are then added to Test Tube C, and a reaction occurs. The students observe bubbles in the resulting solution. After the reaction is complete, the students measure the mass of the substance in Test Tube C.
Less than 35 grams because gases have less mass than solids
Less than 35 grams because gases escaped into the atmosphere during the chemical reaction
Exactly 35 grams because mass is conserved when chemical reactions produce gases
Exactly 35 grams because chemical reactions cause substances to change phases into a gas
Which factor contributes MOST to the formation of a hurricane?
High water temperatures
High water density
High water oxygen levels
High water volume
Many types of plants stand upright when they are healthy and have received plenty of water.
During an extended drought, however, plants often do not have access to enough water. In an arid environment or in an area with frequent droughts, only plants well adapted to the dry conditions will survive long enough to produce seeds. These seeds then sprout and grow into more drought-resistant plants.
Which pair of cell parts are MOST responsible for helping plants stand upright after receiving plenty of water?
Nucleus and ribosome
Cell wall & vacuole
Vacuole & mitochondria
Mitochondria & chloroplast
Match the cell organelle with the correct function of that cell organelle.
mitochondria
cell respiration: convert glucose->ATP
chloroplast
photosynthesis
cell membrane
passage of materials in/out of cell
cell wall
cell protection & structure/rigidity
vacuole
storage of waste/water
Which cell part is most directly involved in the process that allows plants to adapt to drought conditions?
Cell membrane, because it can become more efficient to create drought resistance
Cell nucleus, because it contains information that determines the drought resistant traits passed to next generation
Cell wall, because it adjusts to holding more water, so the next generation of plants can survive droughts
Cell vacuole, because it expands to hold more water making future generations more drought resistant
A student graphs the motion of a toy car moving in a straight line over a 10‑second time period.
Which statement BEST describes the motion of the car?
The car moved at a speed of 5 meters per second for the first 5 seconds, then went at a slower speed for the next 5 seconds.
The car moved at a speed of 5 meters per second for the first 5 seconds, then went at a faster speed for the next 5 seconds.
The car moved at a speed of 1 meter per second for the first 5 seconds, then went at a slower speed for the next 5 seconds.
The car moved at a speed of 1 meter per second for the first 5 seconds, then went at a faster speed for the next 5 seconds.
A student draws models of Earth and the sun in different positions.
Which drawing should be used to represent summer in the Southern Hemisphere?
A student draws models of Earth and the sun in different positions.
Which drawings should be used to represent winter in the Southern Hemisphere?
A student draws models of Earth and the sun in different positions.
Which drawings should be used to represent summer in the Northern Hemisphere?
A student draws models of Earth and the sun in different positions.
Which drawing should be used to represent winter in the Northern Hemisphere?
A teacher adds a colorless solution of potassium iodide to a colorless solution of lead nitrate in a beaker. A yellow solid, precipitate, is observed in the beaker.
Which statement provides the BEST evidence that a chemical reaction occurred and that the law of conservation of mass was observed?
A new substance formed, which caused the mass in the beaker to be increased
A new substance formed, which caused the mass in the beaker did not change
The two substances were mixed together and the solid increased the mass in the beaker
The two substances were mixed together and the solid decreased the mass in the beaker
A balanced chemical equation is shown.
2Fe + 6HC2H3O2 → 2Fe(C2H3O2)3 + 3H2
How many different elements are in the chemical equation?
2
4
13
50
A balanced chemical equation is shown.
2Fe + 6HC2H3O2 → 2Fe(C2H3O2)3 + 3H2
How many hydrogen atoms are in the reactants?
6
18
24
36
A balanced chemical equation is shown.
2Fe + 6HC2H3O2 → 2Fe(C2H3O2)3 + 3H2
How many carbon atoms are in the products?
2
6
12
24
A balanced chemical equation is shown.
2Fe + 6HC2H3O2 → 2Fe(C2H3O2)3 + 3H2
How many total number of oxygen atoms are there in the products?
2
6
12
24
A researcher began the following reaction with 52.6 grams of sugar and Sulfiric Acid in part A. The final mass of the products in part B would MOST LIKELY be:
More than 52.6 grams
Less than 52.6 grams
Exactly 52.6 grams
Cannot be determined
Group 1 uses a balloon to contain gas from a baking soda and vinegar reaction, while Group 2 does not. How would the final mass in Group 2's experiment compare to Group 1's, and why?
The final mass in Group 2's experiment will be greater than Group 1's, because gas is allowed to enter the flask from the room, increasing the final mass.
The final mass in Group 2's experiment will be less than Group 1's, because gas is allowed to escape the flask, decreasing the final mass.
The final mass in Group 2's experiment will be the same as Group 1's, because mass is always conserved during chemical reactions.
The final mass in Group 2's experiment will be greater than Group 1's, because mass is always added during chemical reactions.
In the picture, which box on the right shows the correct products according to the Law of Conservation of Mass?
A
B
C
D
A partial food web is shown.
Which two organisms compete with rabbits for biotic resources?
Select TWO correct answers.
A diagram of a convection current is shown.
Which statement correctly describes the changes in the air as it moves from Location R to Location T?
The Sun heats the land faster than the ocean water, so high-density air moves from the ocean to the land, becoming less dense.
The Sun heats the land faster than the ocean water, so high-density air moves from the land to the ocean, becoming less dense.
The Sun heats the land slower than the ocean water, so high-density air moves from the ocean to the land, becoming less dense.
The Sun heats the land slower than the ocean water, so high-density air moves from the land to the ocean, becoming less dense.
A group of students had two clear solutions, Solution A and Solution B. They poured 30 mL of Solution A and 30 mL of Solution B into a flask, sealed the flask with a stopper, and gently shook it to mix the solutions. The students wrote down their observations and measurements.
-There were 36 g of Solution A and 34 g of Solution B before they were mixed.
-The mass of the empty flask was 300 g.
-The mass of both solutions and the flask was 370 g after the solutions were mixed.
-A precipitate formed when the two solutions were mixed.
-The clear solutions changed to cloudy white after being mixed.
Which statement is evidence that mass was conserved during the chemical reaction?
The volume of each solution was 30 mL before the solutions were mixed.
The total mass of both solutions and the flask was 370 grams before and after the solutions were mixed.
A precipitate formed when the two solutions were mixed.
The mass of solution A was greater the mass of solution B before the solutions were mixed.
Student 1 claims that whenever the color of a substance changes, a chemical change has occurred.
Student 2 claims that food coloring can change the color of a substance without causing a chemical change.
To test their claims, the students add red food coloring to a glass of water. The students observe that the clear water turns a light pink color. Their teacher then runs a test to show that the pink solution contains both water molecules and food-coloring molecules.
Based on these findings, which student is correct?
Student 1, because the food-coloring molecules were found in the pink solution.
Student 1, because the state of matter changed when the food coloring was added.
Student 2, because no new substance was formed when there was a color change
Student 2, because the red food coloring caused the water to change to a pink color.
Two students, Carston and Erikk, push on the opposite sides of a crate, with the force applied by each student in newtons (N), as shown in the diagram.
Assuming the crate is on a frictionless surface in Mr. Cooney's room (which is total lie), which direction will these forces push the crate.
It won't move because Erikk & Carston are too weak to push that much mass. Therefore Mr. Cooney will have to move it by himself.
Carston is stronger than Erikk because he is pushing with more force. Therefore, the crate will move to the right.
Erikk is stronger than Carston because he is pushing with more force, Therefore the crate will move to the left.
Carston & Erikk are of equal strength and push with equal forces in opposite directions. Therefore the crate will not move.
Overfishing reduces the number of fish at a rate that causes long-term reductions in fish populations. The table shows the percentage of fish species in the ocean that were overfished in three different years.
Which action would MOST LIKELY reverse the trend shown in the table?
Increasing the total weight of fish that ships can take from the ocean each day.
Requiring ships to return non-adult fish to the ocean so that they can grow and reproduce.
Decreasing the number of policing ships so that restrictions and regulations on how much fish are taken are leeseened.
Promoting meals centered around specific fish species in order to increase profits.
An astronomer discovers a star that has a temperature of 3,750 K and a luminosity of 103 Lsun.
According to the diagram, which type of star did the astronomer discover?
White dwarf
Main sequence
Super Giant
Giant
An astronomer discovers a star that has a temperature of 3,750 K and a luminosity of 103 Lsun.
Which statement justifies this selection of star?
The star is cool & the brightest compared to other types of stars
The star is hotter & the brightest compared to other types of stars
The star is cool & dim compared to other types of stars
The star is hot & dim compared to other types of stars
A tennis ball is dropped down a stairwell.
Which statement BEST describes the energy of the tennis ball?
The tennis ball's kinetic energy decreases as it falls
The tennis ball has the most potential energy before it is dropped.
The tennis ball has the most kinetic energy as soon as it was dropped.
The tennis balls' potential energy increses as it falls to the ground.
The Olympic Mountains formed along the west coast of the United States at the boundary between the Juan de Fuca Plate and the North American Plate.
Which type of boundary MOST LIKELY exists between the Juan de Fuca Plate and the North American Plate?
Convergent boundary, where the plates are moving towards each other.
Convergent boundary, where the plates are moving parallel to each other.
Transform boundary, where the plates are moving closer to each other.
Transform boundary, where the plates are moving passed each other.
Figure 2 shows the tectonic plate boundary in this area during the Mesozoic Era, which is when the mountains in the Coast Ranges were formed.
Which statement describes the motion of the tectonic plates in Figure 2?
The plates are both moving in the same direction.
The plates are moving away from each other & more oceanic plate is emerging from underneath the continental plate.
The plates are moving towards each other & the oceanic plate is being pushed underneath the continental plate.
The plates are sliding past each other horizontally.
Which statement BEST describes the plate boundary?
Subduction zone at a divergent boundary
Volcanic hot spots at a divergent boundary
Subduction zone at a convergent boundary
Volcanic hot spots at a convergent boundary
Students are learning about tectonic plate activity near the California cities of Oakland and Modesto, which are separated by mountains in the California Coast Ranges. Figure 1 shows a cross section of the area, as well as the general wind pattern blowing over the mountains.
Based on Figure 1, how does Modesto’s weather MOST LIKELY differ from Oakland’s weather?
Modesto will experience less precipitation than Oakland.
Modesto will experience more clouds than Oakland.
The air in modesto will be more humid than the air in Oakland.
The winds in Modesto will move in the opposite direction than the winds in Oakland.
A student sets a 0.4 kilogram (kg) soccer ball on the ground and gives it a hard kick. The ball traveled a distance of 37 meters (m). The acceleration of the ball was 2,550 meters per second squared (m/s2).
Based on the data, how much force in newtons (N) did the student apply to the ball?
14.8 N
68.9 N
1020.0 N
6375.0 N
