Elements

Carbon is considered an element, while carbon dioxide is considered a compound. This is because carbon dioxide is

• a gas at room temperature.

• made up of two different elements.

• given off by green plants.

• useful to human beings.

Which of the following is the most abundant element on the Earth's crust?

• Calcium

• Iron

• Oxygen

• Potassium

Compounds are different than elements because compounds are

• combinations of two or more elements.

• not able to be broken down into parts.

• made from the same type of atoms.

• a pure substance, elements are not.

Which of the following three elements are most abundant in the plants and animals that make up the biosphere?

• Sulfur, oxygen, and hydrogen

• Nitrogen, silicon, and oxygen

• Phosphorous, oxygen, and iron

• Oxygen, carbon, and hydrogen

The smallest particle of any particular type of matter is known by which of the following terms?

• Element

• Chemical

• Atom

• Compound

The oceans are primarily composed of which two elements?

• Carbon and hydrogen

• Calcium and silicon

• Hydrogen and oxygen

• Nitrogen and phosphorus

Which two elements are the most common in the rocky outer surface that makes up Earth’s lithosphere?

• Silicon and oxygen

• Oxygen and hydrogen

• Nitrogen and oxygen

• Oxygen and carbon

All of the following elements are major components of living things on Earth EXCEPT

• nitrogen

• carbon

• sulfur

• oxygen

The atmosphere of Earth is comprised mostly of oxygen and -

• carbon

• silicon

• hydrogen

• nitrogen

All of the following elements make up most living things on Earth EXCEPT –

• carbon.

• silicon.

• hydrogen.

• oxygen.