By Murray Shukyn, Dale E. Shuttleworth, Achim K. Krull

The following GED Science practice questions test your knowledge of basic science concepts. Many questions you encounter may include charts or other visual aids and ask you to interpret the information given. Pace yourself and answer each question as best you can.

Sample questions

Give the following science questions a try.

Passage A

Biofuels are gas or liquid fuels made from plant material (biomass). They include wood, wood waste, wood liquors, peat, railroad ties, wood sludge, spent sulfite liquors, agricultural waste, straw, tires, fish oils, tall oil, sludge waste, waste alcohol, municipal solid waste, landfill gases, other waste, and ethanol blended into motor gasoline.

  1. Biofuels are ecologically sound because

    • (A) they are inexpensive

    • (B) they do not pollute the earth

    • (C) they are made from recyclable materials

    • (D) they can be used as fuels

Passage B

Carbon footprint is the total amount of greenhouse gases that are emitted into the atmosphere each year by a person, family, building, organization, or company. A person’s carbon footprint includes greenhouse gas emissions from fuel that an individual burns directly, such as by heating a home or riding in a car.

It also includes greenhouse gases that come from producing the goods or services that the individual uses, including emissions from power plants that make electricity, factories that make products, and landfills where trash gets sent.

  1. People could reduce their individual carbon footprint by

    • (A) driving their cars less

    • (B) lowering their thermostats during the cold weather

    • (C) not barbequing meat

    • (D) all of the above

  2. People’s personal carbon footprint is also affected by processes out of their control, such as

    • (A) grocery shopping

    • (B) recycling depots

    • (C) power plants

    • (D) all of the above

Passage C

The most abundant greenhouse gas, water vapor is the water present in the atmosphere in gaseous form. Water vapor is an important part of the natural greenhouse effect. While humans are not significantly increasing its concentration through direct emissions, it contributes to the enhanced greenhouse effect because the warming influence of greenhouse gases leads to a positive water vapor feedback.

In addition to its role as a natural greenhouse gas, water vapor also affects the temperature of the planet because clouds form when excess water vapor in the atmosphere condenses to form ice and water droplets and precipitation.

  1. Water vapor is a positive influence on the earth because

    • (A) it moisturizes your skin

    • (B) it counteracts carbon emissions

    • (C) it has a positive effect on the temperature of earth

    • (D) it cools the mountains

Passage D

Saving lives does not have to be as complex as robotic surgery, but can be as simple as providing the life-giving source of clean water. This specifically is of utmost importance to a community in rural Mexico, showing the far-reaching benefits of the water purification component of NASA’s Environmental and Life Control Support System (ECLSS).

ECLSS provides clean water for drinking, cooking and hygiene aboard the space station. This technology has been adapted on Earth to aid remote locations or places devastated by natural disaster that do not have access to clean drinking water.

In Chiapas, Mexico, many people are at risk of illness from drinking contaminated water from wells, rivers or springs not treated by municipal water systems. Children in Chiapas, previously sickened by parasites and stomach bugs, now have access during school to clean, safe drinking water. This is due to the installation of the ECLSS-derived water purification plant.

Renewable solar energy powers the water treatment technology for the community in Chiapas. Results include improved overall health and cost-savings from not having to buy purified water or medication to treat water-borne illnesses.

  1. How do innovations by NASA help a little town in Mexico?

    • (A) by setting up space industries

    • (B) by providing for clean water

    • (C) by supplying food

    • (D) by ridding the area of parasites


Compare your answers to the answers below for accuracy.

Passage A

  1. B. they do not pollute the earth. Materials made from biomass tend to be made from recycled materials, making them less polluting.

Passage B

  1. D. all of the above. Driving your car less, lowering your thermostat during the cold weather, and not barbequing meat all would reduce your carbon footprint.

  2. C. power plants. Power plants may increase or decrease pollution depending on the process used, which tends to affect your carbon footprint positively or negatively.

Passage C

  1. C. it has a positive effect on the temperature of earth. The passage states that water vapor affects the temperature of the earth.

Passage D

  1. B. by providing for clean water. NASA used a form of its water purification process to provide the village with clean water.