Question 1

Which property of carbon allows it to form a wide variety of complex molecules essential for life?

Accepted Answer

Its tetravalence, allowing it to form four covalent bonds

Question 2

Given the electron configuration of carbon ($$1s^2$$ $$2s^2$$ $$2p^2$$), how many unpaired electrons does it have in its valence shell, and what does this imply about its bonding capacity?

Accepted Answer

4 unpaired electrons; can form four bonds

Question 3

Which of the following best describes a structural isomer?

Accepted Answer

Molecules with the same molecular formula but different connectivity of atoms

Question 4

A patient is prescribed albuterol for asthma. Why is it important that the medication is the R-enantiomer and not the S-enantiomer?

Accepted Answer

The R-enantiomer is effective at improving airflow, while the S-enantiomer is ineffective

Question 5

Which functional group is present in all alcohols and is responsible for their solubility in water?

Accepted Answer

Hydroxyl group ($$-OH)$$

Question 6

Which of the following molecules contains a carbonyl group attached to two other carbons, and what is its general class?

Accepted Answer

Acetone; ketone

Question 7

Which functional group is crucial for energy transfer in cells, as seen in ATP?

Accepted Answer

Phosphate group ($$-$$OPO_3$$^{2-})$$

Question 8

Which type of isomerism is illustrated by D-glucose and L-glucose?

Accepted Answer

Enantiomerism

Question 9

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

Accepted Answer

Structural isomerism

Question 10

Which of the following functional groups acts as a weak acid and is commonly found at the end of fatty acid chains?

Accepted Answer

Carboxyl group ($$-COOH)$$

Question 11

Which functional group is found in cysteine and is important for stabilizing protein structure through disulfide bonds?

Accepted Answer

Sulfhydryl group ($$-SH)$$

Question 12

Which of the following statements about geometric (cis-trans) isomers is correct?

Accepted Answer

They differ in the arrangement of groups around a double bond

Question 13

Testosterone and estradiol differ in their biological activity due to the presence of which type of chemical group?

Accepted Answer

Different functional groups attached to the same carbon skeleton

Question 14

Which of the following is true about the amino group ($$-NH_2$)?

Accepted Answer

It acts as a weak base

Question 15

A molecule contains a carbon atom bonded to an oxygen atom by a double bond and to a hydrogen atom. What functional group does this describe?

Accepted Answer

Aldehyde

Question 16

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

Accepted Answer

Carbon's tetravalence allows it to form stable, diverse covalent bonds

Question 17

Which functional group, when added to cytosine, decreases its solubility in water and increases its non-polar character?

Accepted Answer

Methyl group ($$-CH_3$)

Question 18

Which of the following is a real-world example of the importance of enantiomers in medicine?

Accepted Answer

Ibuprofen: only the S-enantiomer reduces inflammation and pain

Question 19

Which of the following best describes the difference between aldehydes and ketones?

Accepted Answer

Aldehydes have a carbonyl group at the end of the carbon chain; ketones have it within the chain

Chapter 4: Carbon and the Molecular Diversity of Life – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards