Question 1

Which property of carbon most directly explains its ability to form large, complex, and diverse molecules essential for life?

Accepted Answer

Carbon has four valence electrons, allowing it to form up to four covalent bonds with other atoms.

Question 2

Which of the following best describes a hydrocarbon?

Accepted Answer

A molecule composed only of carbon and hydrogen atoms.

Question 3

Which of the following is NOT a way that carbon skeletons can vary?

Accepted Answer

Type of ionic charge on the carbon atoms

Question 4

Which type of isomerism is responsible for molecules that are mirror images of each other, such as L-dopa and D-dopa?

Accepted Answer

Enantiomerism

Question 5

A molecule with the formula $$C_5H_{12}$$ can exist as both a straight chain and a branched chain. What type of isomers are these?

Accepted Answer

Structural isomers

Question 6

Which functional group is present in all amino acids and is responsible for their basic properties?

Accepted Answer

Amino group ($$-NH_2$)

Question 7

Which of the following best explains why only one enantiomer of a drug may be biologically active?

Accepted Answer

Biological systems are sensitive to the spatial arrangement of atoms in molecules.

Question 8

Which of the following diagrams would best show the three-dimensional shape of a molecule?

Accepted Answer

Space-filling model

Question 9

Which functional group is found in ATP and is key to its role in energy transfer within cells?

Accepted Answer

Phosphate group ($$-PO_4$^{2-})$$

Question 10

Which of the following statements about hydrocarbons is TRUE?

Accepted Answer

Hydrocarbons can release a large amount of energy when they undergo chemical reactions.

Question 11

A molecule contains a carbon atom double-bonded to an oxygen atom. Which functional group does this describe?

Accepted Answer

Carbonyl group

Question 12

Which of the following best describes the difference between cis-trans isomers?

Accepted Answer

They differ in the spatial arrangement of atoms around a double bond.

Question 13

Which of the following is a property of the carboxyl group ($$-COOH$$)?

Accepted Answer

It acts as an acid by donating protons.

Question 14

Which of the following best explains why carbon is considered the backbone of biological molecules?

Accepted Answer

Carbon can form stable covalent bonds with many elements, including itself, allowing for a great diversity of molecular structures.

Question 15

Which of the following best describes the role of ATP in the cell?

Accepted Answer

ATP stores potential energy in its phosphate bonds, which is released when it reacts with water.

Question 16

Which of the following is NOT a functional group commonly found in organic molecules?

Accepted Answer

Chloride group

Question 17

A molecule has the formula $$C_3H_8. $$Which of the following statements is TRUE about this molecule?

Accepted Answer

It is a hydrocarbon and can undergo reactions that release energy.

Question 18

Which of the following best explains why enantiomers can have different effects in biological systems?

Accepted Answer

They have different spatial arrangements, which can interact differently with enzymes and receptors.

Question 19

Which of the following best describes the structure of estradiol and testosterone?

Accepted Answer

They have the same carbon skeleton but differ in the functional groups attached.

Question 20

Which of the following statements about organic chemistry is TRUE?

Accepted Answer

Organic chemistry is the study of compounds that contain carbon, regardless of their origin.

Carbon and the Molecular Diversity of Life: Study Notes for GOB Chemistry

Study Guide - Practice Questions