Question 1

Which statement best explains why carbon is considered the backbone of life?

Accepted Answer

Carbon atoms can form up to four covalent bonds, allowing for a diversity of stable, complex molecules.

Question 2

A sample of iron has the atomic number 26. What is the correct composition of its subatomic particles?

Accepted Answer

26 electrons, 26 protons, and 26 neutrons.

Question 3

Carbon has four electrons in its valence shell. What type(s) of covalent bonds can it form with oxygen?

Accepted Answer

Single and double bonds

Question 4

Which experiment demonstrated that organic molecules could be synthesized from inorganic precursors under early Earth conditions?

Accepted Answer

The Miller-Urey experiment

Question 5

Which of the following best describes a hydrocarbon?

Accepted Answer

A molecule consisting only of carbon and hydrogen

Question 6

Which chemical group is responsible for making a molecule an acid by donating a hydrogen ion ($$H^+$$)?

Accepted Answer

Carboxyl group ($$-COOH)$$

Question 7

Which type of isomer has the same molecular formula but differs in the spatial arrangement around a double bond?

Accepted Answer

Cis-trans isomer

Question 8

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

Accepted Answer

Phosphate group ($$-PO_4$)

Question 9

A molecule with the formula $$C_5H_{12}$$ can exist as pentane or 2-methylbutane. What type of isomerism does this illustrate?

Accepted Answer

Structural isomerism

Question 10

Which property of hydrocarbons makes them a major component of fossil fuels?

Accepted Answer

They store large amounts of energy in their C-H bonds.

Question 11

Which chemical group is directly involved in gene expression and can control when a gene is 'turned off'?

Accepted Answer

Methyl group ($$-CH_3$)

Question 12

Which functional group is found in alcohols and is responsible for their ability to form hydrogen bonds with water?

Accepted Answer

Hydroxyl group ($$-OH)$$

Question 13

Which type of isomerism is exhibited by molecules that are mirror images of each other and have an asymmetric carbon?

Accepted Answer

Enantiomerism

Question 14

Which chemical group is found in amino acids and can act as a base by picking up a hydrogen ion ($$H^+$$)?

Accepted Answer

Amino group ($$-NH_2$)

Question 15

Which functional group is responsible for forming disulfide bonds that stabilize protein structure?

Accepted Answer

Sulfhydryl group ($$-SH)$$

Question 16

Which of the following is a correct description of a cis isomer?

Accepted Answer

The two substituents are on the same side of a double bond.

Question 17

Which chemical group is NOT chemically active but can affect the shape and function of molecules?

Accepted Answer

Methyl group ($$-CH_3$)

Question 18

Which of the following best explains why carbon can form such a wide variety of molecules?

Accepted Answer

Carbon can form up to four covalent bonds with other atoms, including single, double, and triple bonds.

Question 19

Which chemical group is commonly found in sugars and is responsible for their solubility in water?

Accepted Answer

Hydroxyl group ($$-OH)$$

Question 20

Which of the following is a real-world application of the concept of isomers in medicine?

Accepted Answer

Enantiomers of a drug can have different effects in the body, such as one being therapeutic and the other being harmful.

Carbon and the Molecular Diversity of Life: Study Notes

Study Guide - Practice Questions