8th Grade Science 2019 PSSA Sampler

A student learns that pure water freezes at 0°C. The student wants to find out how much salt needs to be added to the water to lower the freezing temperature by two degrees. Which statement explains why this question can be answered through scientific inquiry?

• The question likely has more than one answer.

• The question has already been answered by scientists.

• The question can be investigated through a group of experiments.

• The question can be answered through mathematical calculations.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Scientists recently discovered that firing low-energy particles at potatoes keeps the potatoes from developing unwanted sprouts. They observed that these energy particles prevent cell division in the sprouts. This stops the potatoes from sprouting for up to 120 days. How will this development most likely affect the potato industry?

• by allowing food engineers to improve the ways potatoes can be prepared

• by allowing potatoes to ripen over a longer period of time to improve flavor

• by allowing potatoes to be stored longer so they can be sold during winter months

• by allowing faster transportation to supermarkets so they never run out of potatoes

Tags

NGSS.MS-ETS1-1

NGSS.MS-LS2-4

A student predicts that a solution of ethanol (C2H5OH) and water will have a lower density at room temperature than that of pure water. Which tools would most help the student test this prediction?

• a meterstick and a balance

• a hot plate and a thermometer

• a thermometer and a stopwatch

• a balance and a graduated cylinder

Which statement explains why populations in upper trophic levels tend to have less total mass than populations in lower trophic levels?

• Populations in upper trophic levels are more complex than populations in lower trophic levels.

• Populations in upper trophic levels have less available habitat than populations in lower trophic levels.

• Populations in upper trophic levels have less available energy than populations in lower trophic levels.

• Populations in upper trophic levels have more nutrient requirements than populations in lower trophic levels.

Tags

NGSS.MS-LS2-3

NGSS.MS-LS2-1

Which statement best explains why the carbon cycle is classified as a closed-loop system?

• Carbon levels are monitored and maintained by plants in a system

• The flow of carbon occurs only in nonliving components of a system.

• Earth’s atmosphere traps all carbon once it passes through living organisms in a system.

• A fixed amount of carbon flows between the living and nonliving components of a system.

Tags

NGSS.MS-LS2-3

A mouse’s habitat is a grassland containing rocks, soil, and grass. The mouse lives in a burrow underground. Based on this information, which statement best describes how the mouse interacts with its environment?

• The mouse uses soil for food and shelter

• The mouse gets energy from its predators.

• The mouse changes its environment to create food.

• The mouse gets energy and shelter from its environment.

Which relationship would a scientist most likely model using calculations based on the law of universal gravitation?

• the motion of planets within the solar system

• the internal structure and position of the Moon

• factors that affect Earth’s atmosphere and climate

• . natural events that change the shape of Earth’s surface

Tags

NGSS.MS-ESS1-2

NGSS.MS-ESS1-1

A scientist measured dissolved oxygen (O2) levels in a pond over time. A graph showing the results of the measurements is shown. Which statement is the most accurate description of the events occurring in the pond during the time shown?

• Aquatic plants consume O2 in the pond through respiration at a constant level.

• Aquatic plants consume O2 in the pond through respiration mostly during the early morning.

• Aquatic plants provide additional O2 for the pond through photosynthesis from late afternoon to early morning.

• Aquatic plants provide additional O2 for the pond through photosynthesis from early morning until late afternoon.

Tags

NGSS.MS-LS2-3

NGSS.MS-LS2-1

NGSS.MS-LS1-6

Biodiesel is an alternative fuel to traditional diesel. Both produce the same amount of energy. Which statement best compares biodiesel to traditional diesel?

• Biodiesel produces no carbon dioxide, while traditional diesel produces large amounts of the gas.

• Biodiesel produces a small amount of hydrogen, while traditional diesel produces large amounts of the gas.

• Biodiesel is produced from a material that forms over a few months, while traditional diesel is produced from a material that forms over several million years.

• Biodiesel is produced from a material that forms over several decades, while traditional diesel is produced from a material that forms over a few thousand years.

Tags

NGSS.MS-PS1-3

Many people in Pennsylvania depend on groundwater for their water supply. Which action would most likely provide a greater amount of groundwater?

• an increase in the amount of infiltration

• a decrease in the amount of condensation

• an increase in the amount of developed land surface

• a decrease in the amount of autumn and winter precipitation

Tags

NGSS.MS-ESS2-4

NGSS.MS-ESS3-1