Question 1

Which property of water is primarily responsible for the phenomenon of surface tension, allowing insects like water striders to walk on water?

Accepted Answer

Cohesion due to hydrogen bonding between water molecules

Question 2

Carbon is described as tetravalent. What does this mean in terms of its bonding capabilities?

Accepted Answer

Carbon can share four pairs of electrons, forming four covalent bonds

Question 3

Which functional group is responsible for making molecules more hydrophilic and increasing their solubility in water?

Accepted Answer

Hydroxyl group ($$-OH)$$

Question 4

A molecule of water ($$H_2O) is $$described as polar. Which statement best explains this polarity?

Accepted Answer

The oxygen atom is more electronegative, pulling shared electrons closer and creating partial charges

Question 5

Which type of bond involves the sharing of electrons unequally between atoms, resulting in partial charges?

Accepted Answer

Polar covalent bond

Question 6

What is the main reason why oil does not mix with water?

Accepted Answer

Oil molecules are nonpolar and water is polar

Question 7

Which functional group is found in ATP and is crucial for energy transfer in biological systems?

Accepted Answer

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

Question 8

A student mixes salt ($$NaCl) in $$water and observes it dissolves easily. Which property of water allows it to dissolve ionic compounds like salt?

Accepted Answer

Water's polarity and ability to form hydration shells around ions

Question 9

Which of the following is NOT a property that emerges from the structure of water?

Accepted Answer

Ability to dissolve nonpolar molecules

Question 10

Which statement best describes the difference between cis- and trans-isomers?

Accepted Answer

Cis-isomers have functional groups on the same side of a double bond, trans-isomers on opposite sides

Question 11

Which functional group acts as a biological base and is found in amino acids?

Accepted Answer

Amino group ($$-NH_2$)

Question 12

A molecule contains both a carboxyl group and an amino group. What type of molecule is this most likely to be?

Accepted Answer

A protein (amino acid)

Question 13

Which of the following best explains why water has a high specific heat capacity?

Accepted Answer

Hydrogen bonds between water molecules require significant energy to break

Question 14

Which type of bond is formed between two oppositely charged ions, such as $$Na^+$$ and $$Cl^- in $$table salt?

Accepted Answer

Ionic bond

Question 15

Which functional group is nonpolar and often affects gene expression when added to DNA?

Accepted Answer

Methyl group ($$-CH_3$)

Question 16

Which property of water allows it to move upward through the roots and stems of plants against gravity?

Accepted Answer

Cohesion and adhesion working together

Question 17

Which of the following is a correct statement about electronegativity?

Accepted Answer

Electronegativity is determined by the number of protons in the nucleus and the number of valence electrons

Question 18

Which functional group is found in sugars and is responsible for their reactivity?

Accepted Answer

Aldehyde group ($$-CHO)$$

Question 19

Which of the following best describes a hydrogen bond?

Accepted Answer

An attraction between a hydrogen atom and an electronegative atom to which it is not covalently bonded

Question 20

Which functional group is acidic and found in fatty acids?

Accepted Answer

Carboxyl group ($$-COOH)$$

Chemistry in Biology: Atomic Structure, Chemical Bonds, Water Properties, and Functional Groups

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