TCAP Fourth Science

A student was reading about the gases in air. Ozone helps protect Earth from harmful ultraviolet rays that come from the sun. Certain types of pollution created by humans have caused a hole in the ozone layer. This hole is over the South Pole and could become larger if this type of pollution increases.

Which question should the student ask to determine if ozone is an elemental molecule?

• What is the color of the molecule?

• What is the shape of the molecule?

• What elements are present in the molecule?

• How many atoms are present in the molecule?

Tags

NGSS.MS-PS1-1

The table shows the estimated percent concentrations of atmospheric gases. Trace gases are composed of small amounts of gases such as carbon dioxide, water vapor, and methane. Which of these will most likely increase the amount of a trace gas in the

atmosphere?

• A pine cone releases the protected seeds inside after it is exposed to intense

  heat.

• A hydroelectric dam increases the amount of water processed into energy after a flood.

• A company refining uranium ore is powered by natural gas.

• A bacterium releases oxygen gas during photosynthesis.

A Tennessee student studying the carbon cycle learned that carbon moves through all four spheres of Earth: the atmosphere, the hydrosphere, the biosphere, and the geosphere. The student wanted to understand how carbon cycles through both the abiotic and biotic parts of the planet.

The student knew that limestone, the official state rock of Tennessee, contains carbon because it is made of calcium carbonate (CaCO3). The student learned that the water (H2O) in the ocean absorbs carbon dioxide (CO2) from the atmosphere. This produces carbonic acid (H2CO3), which easily splits apart into +− hydrogen ions (H ) and bicarbonate ions (HCO3 ), which are both charged particles. The chemical reaction for this process is shown. The bicarbonate ions (HCO3 ) split into more hydrogen ions (H ) and carbonate ions (CO32−). Corals and mollusks pull in seawater that contains the carbonate ions and

2+calcium ions (Ca ) and pump out any hydrogen ions. The organisms use the carbonate and calcium ions to make calcium carbonate (CaCO3) for their skeletons and shells.

When the corals and mollusks die, layers of their skeletons and shells form on the ocean floor. As the layers are buried by sediments, they compact and cement to form

limestone, which is a sedimentary rock made of calcium carbonate (CaCO3). Which step in the formation of limestone includes biotic parts of the system?

• 1. Carbon dioxide in the atmosphere

• 2. Water in the ocean that contains carbon dioxide

• 3. Calcium carbonate in shells and corals

• 4. Calcium carbonate in limestone

Tags

NGSS.MS-LS2-3

NGSS.MS-LS2-4

After learning about limestone formation in a marine environment, the student was still curious about the cycling of carbon through the biotic and abiotic parts of the planet in a terrestrial environment. The student found a diagram on the website that shows another way that carbon in the atmosphere is absorbed into another part of the planet. This diagram shows the carbon moving directly into the biosphere. The student learned that plants absorb carbon dioxide from the atmosphere and use it for photosynthesis. During photosynthesis, plants make sugars that are used by the plant for growth and that are stored for energy. Animals eat the plants for food and absorb the carbon in the sugar. When the plants and animals die, their bodies decay, releasing carbon into the soil. Under the right conditions, decaying plants can turn into coal, which is almost pure carbon. Eastern Tennessee has several coal mines that produce tons of coal each year. This coal is burned for energy, which releases carbon dioxide back into the atmosphere. Coal is mostly carbon. When coal is burned, it reacts with oxygen. The carbon dioxide produced is released into the atmosphere. The chemical reaction for coal burning is shown.

C + O2 → CO2

Based on the model shown, which statement correctly describes what may happen to the carbon dioxide in the atmosphere?

• Carbon dioxide becomes solid and falls to the ground.

• Carbon dioxide burns in the atmosphere.

• Carbon dioxide is used by plants in photosynthesis.

• Carbon dioxide is breathed in by animals and humans.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

The student learns that carbon dioxide is stored in Earth’s mantle. Which part of the carbon cycle diagram shows the carbon dioxide from the mantle being cycled to another sphere of Earth?

• the arrow pointing from the volcano, which is part of the geosphere, to the atmosphere

• the arrow pointing from the plant, which is part of the biosphere, to the soil, which is part of the geosphere

• the arrow pointing from the plant, which is part of the biosphere, to the animal, which is also part of the biosphere

• the arrow pointing from the coal, which is part of the geosphere, to the factory, which releases emissions into the atmosphere

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

Which statement best classifies air?

• Air is a pure substance because it is composed of pure substances.

• Air is a pure substance because its properties rarely change.

• Air is a mixture because it has the same properties at all times.

• Air is a mixture because its composition varies.

Which statement does not describe a problem that causes some smaller cities to have poorer air quality than some larger cities?

• Smaller cities have less funding to spend fighting pollution.

• Smaller cities have fewer charging stations for electric cars.

• Smaller cities have shorter commutes to work.

• Smaller cities have less access to public transportation.

Which question about photochemical smog could not be experimentally determined by scientists?

• In what year will the amount of sulfur in the air start to decrease?

• How many different types of hydrocarbons are found in gasoline?

• What concentration of gas molecules causes a visible brown haze in the air?

• What temperature is the car engine when it begins to produce nitric oxide in the cylinder?

Tags

NGSS.MS-PS1-2

One of the components contained in gasoline is octane C8H18 . Which () statement best describes C8H18?

• It is a mixture containing a combination of the properties of hydrogen and carbon.

• It is a pure substance containing a combination of the properties of hydrogen and carbon.

• It is a mixture containing properties different from those of hydrogen and carbon.

• It is a pure substance containing properties different from those of hydrogen and carbon.

Tags

NGSS.MS-PS1-1

Students learn that impurities in hydrocarbons release sulfur into the air, which contributes to smog. Which recommendation will least likely reduce the amount of sulfur released into the air?

• driving a smaller car that gets better gas mileage

• filling the vehicle up with gas at the same gas station each time

• treating the fuel to remove the impurities

• riding with neighbors to go to school and work