Question 1

Which of the following best describes a hydrogen bond?

Accepted Answer

An attractive intermolecular force between partial charges of opposite polarity, typically involving hydrogen and electronegative atoms like oxygen or nitrogen.

Question 2

Which of the following macromolecules is NOT one of the four essential for life?

Accepted Answer

Vitamins

Question 3

A solution has a hydrogen ion concentration of $$1 	imes 10$$^{-5}$$ M. What is its pH?

Accepted Answer

$$5$$

Question 4

Which of the following statements about covalent bonds is TRUE?

Accepted Answer

Covalent bonds involve the sharing of electron pairs between atoms.

Question 5

Which element is capable of forming four covalent bonds, making it essential for the structure of macromolecules?

Accepted Answer

Carbon

Question 6

A scientist is studying a molecule that is formed by dehydration synthesis. Which of the following best describes what is happening during this process?

Accepted Answer

Water is removed to form a bond between two monomers.

Question 7

Which of the following best explains why water is considered a polar molecule?

Accepted Answer

It has a partial negative charge near the oxygen atom and a partial positive charge near the hydrogen atoms.

Question 8

If a solution has a pH of 3, how many times more acidic is it than a solution with a pH of 6?

Accepted Answer

$$1000$$ times

Question 9

Which of the following is a correct statement about ionic bonds?

Accepted Answer

Ionic bonds are formed when electrons are transferred from one atom to another.

Question 10

A biologist adds a substance to a solution, and the pH increases from 6 to 8. What has most likely been added?

Accepted Answer

A base

Question 11

Which of the following best describes hydrolysis in biological systems?

Accepted Answer

The addition of water to break a bond between two molecules.

Question 12

Which of the following is the correct formula for calculating pH?

Accepted Answer

$$\mathrm{pH} = -\log[H^+]$$

Question 13

Which of the following scenarios best illustrates the importance of hydrogen bonding in biology?

Accepted Answer

The double helix structure of DNA stabilized by bonds between nitrogenous bases.

Question 14

Which of the following statements about the pH scale is correct?

Accepted Answer

A solution with pH 7 is neutral, having equal concentrations of $$[H^+]$$ and $$[OH^-].$$

Question 15

Which of the following best explains why carbon is so important in biological molecules?

Accepted Answer

It can form up to four covalent bonds, allowing for complex and diverse molecular structures.

Question 16

A molecule of methane ($$CH_4) is $$formed when carbon shares electrons with four hydrogen atoms. What type of bond is formed between carbon and hydrogen in methane?

Accepted Answer

Non-polar covalent bond

Question 17

Which of the following is a real-life example of hydrolysis?

Accepted Answer

Digestion of starch into glucose molecules in the human intestine.

Question 18

Which of the following best describes the difference between polar and non-polar covalent bonds?

Accepted Answer

Polar covalent bonds involve unequal sharing of electrons, resulting in partial charges, while non-polar covalent bonds involve equal sharing.

Question 19

A solution has a hydroxide ion concentration of $$1 	imes 10$$^{-9}$$ M. What is the pH of the solution?

Accepted Answer

$$14 - 9 = 5$$

Question 20

Which of the following best explains why ionic compounds like NaCl dissolve easily in water?

Accepted Answer

Water molecules surround and separate the ions due to their polarity.

Chapter 02: The Chemistry of Biology – Foundations for Microbiology

Guida di studio - Domande di pratica

Study guide - Flashcard