Online Access Free GED-Science Exam Questions

The pH of a liquid is a measure of its acidity or its alkalinity. Even small changes in pH of human blood can cause very serious health problems.
Carbon dioxide (CO2), is one of the dissolved gases present in healthy blood. CO2 normally mixes with the water in blood to form a mild acid, carbonic acid, which lowers the blood pH.If a health problem causes the dissolved carbon dioxide to increase or decrease, the blood's pH would change and could produce an unhealthy pH level.
Based on this information, which statement best summarizes the blood condition that might result when an individual has a respiratory condition that causes the blood to contain too much CO2?

• A.The blood will be less acidic.
• B.The blood's white cell count will be greatly decreased.
• C.The blood pH will be lowered.
• D.The blood will clot more quickly.
• E.The blood pH will remain the same.

Which is a useful way of reducing acidification of a lake?

• A.stocking the lake with large fish
• B.adding phosphates to the surrounding soil
• C.increasing acid emissions from a local power plant
• D.decreasing the lake's plants
• E.adding calcium compounds to the lake water

All kerosene stoves produce carbon monoxide and carbon dioxide gases as by-products of combustion. Both gases are dangerous to human beings.
When using a kerosene stove, which action provides the best protection against these harmful gases?

• A.locating the stove far from walls and furniture
• B.using only the correct grade of kerosene
• C.keeping a fire extinguisher near the stove
• D.circulating air around the room with a fan
• E.keeping the room well ventilated

Science is a systemized body of knowledge based on observation and experimentation. Technology involves applied science and the practical applications of scientific knowledge. The making of lenses for eyeglasses is a technology that is based on the scientific principles of optics explaining how light rays are bent by finely ground lenses.
Which example would be considered science rather than technology?

• A.can opener
• B.fishing rod
• C.microscope
• D.seesaw
• E.structure of the atom

Gases are one of three common states of matter and are affected by changes in temperature, volume, and pressure. When the pressure of a gas in a closed container becomes too high, it can cause the container to burst. The graph below illustrates the relationship between pressure and temperature (K) for ordinary gases.

Aerosol cans contain a pressurized gas that is used to propel, or spray, the contents out of the can. Many aerosol cans have labels that warn the users against incinerating (burning) them because of the danger of explosion.
What would happen to the pressure of the gas if the temperature inside the can increases?

• A.vary
• B.remain the same
• C.increase
• D.decrease
• E.increase, and then decrease