$$C_6H_{12}O_6$ + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{energy}$$

Question 1

Which of the following best describes an element as defined in the context of chemistry?

Accepted Answer

A pure substance that cannot be broken down into simpler chemical entities by ordinary chemical reactions.

Question 2

Which set of elements makes up the majority of biological molecules in living things (CHONPS)?

Accepted Answer

Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur

Question 3

A carbon atom has an atomic number of 6 and an atomic mass of 12. How many neutrons does it have?

Accepted Answer

$$12 - 6 = 6$$ neutrons

Question 4

Which of the following is an example of a compound?

Accepted Answer

NaCl (table salt)

Question 5

What type of bond is formed when electrons are transferred from one atom to another?

Accepted Answer

Ionic bond

Question 6

Which of the following best explains why water is considered a 'universal solvent'?

Accepted Answer

Water's polarity allows it to dissolve many different substances.

Question 7

A solution has a pH of 3. How does its hydrogen ion concentration compare to a solution with a pH of 6?

Accepted Answer

It is $$10^{6-3}$$ = $$10^3 = 1000$ times higher.

Question 8

Which of the following is a correct example of a chemical synthesis reaction?

Accepted Answer

$$A + B \rightarrow AB$$

Question 9

Which property of water is most responsible for the cooling effect of sweating in humans?

Accepted Answer

High heat of vaporization

Question 10

A patient’s blood pH drops from 7.4 to 7.1. Which buffer system reaction would help restore normal pH?

Accepted Answer

$$HCO_3^- + H$$^+ \rightarrow H_2CO_3$$

Question 11

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons

Question 12

Which of the following is a correct representation of an exergonic reaction?

Accepted Answer

$$C_6H_{12}O_6$ + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{energy}$$

Question 13

Which of the following is a property of acids?

Accepted Answer

They are proton donors.

Question 14

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electrons between atoms.

Question 15

Which of the following is a correct example of a buffer in the human body?

Accepted Answer

Bicarbonate ($$HCO_3$$^-$$)

Question 16

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

Accepted Answer

Hydrogen bonding between water molecules allows them to absorb and release large amounts of heat.

Question 17

A sodium atom (Na) loses one electron to become a sodium ion (Na$$^+). $$What is the resulting charge and why?

Accepted Answer

Positive, because it has more protons than electrons.

Question 18

Which of the following is a real-life example of a neutralization reaction?

Accepted Answer

$$HCl + NaOH \rightarrow H_2O + NaCl$$

Question 19

Which of the following best describes the function of a buffer in biological systems?

Accepted Answer

It resists dramatic changes in pH by neutralizing excess acids or bases.

Question 20

Which of the following is a correct example of a chemical decomposition reaction?

Accepted Answer

$$AB \rightarrow A + B$$

The Chemical Context of Life: Elements, Atoms, and Water in Anatomy & Physiology

Study Guide - Practice Questions