Question 1

Which of the following best explains why ice floats on liquid water?

Accepted Answer

Hydrogen bonds in ice hold water molecules farther apart, making ice less dense than liquid water.

Question 2

A solution has a pH of 5. Compared to a solution with pH 8, how many times more hydrogen ions ($$H^+) $$does it contain?

Accepted Answer

$$1000$$ times more $$H^+$$ ions

Question 3

Which major biological theme is illustrated by the process in which cells rearrange molecules by breaking existing chemical bonds and forming new ones?

Accepted Answer

Pathways that transform energy and matter

Question 4

What type of chemical bond is formed when a lithium ion ($$Li^+) $$joins a bromide ion ($$Br^-) to $$form lithium bromide?

Accepted Answer

Ionic bond

Question 5

Which of the following is a trace element essential for human life, and its deficiency can lead to goiter?

Accepted Answer

Iodine

Question 6

Which property of water allows trees to transport water from their roots to their leaves?

Accepted Answer

Cohesion due to hydrogen bonding

Question 7

Radioactive isotopes are useful in medicine and evolutionary studies because:

Accepted Answer

Their nuclei decay spontaneously, allowing for dating fossils and targeting cancer cells.

Question 8

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of one or more pairs of electrons between atoms.

Question 9

If a molecule of sulfur trioxide ($$SO_3) $$combines with a molecule of water ($$H_2O) to $$produce a single product, what is the formula of the product?

Accepted Answer

$$H_2SO_4$$

Question 10

Which of the following statements about elements and compounds is correct?

Accepted Answer

A compound contains two or more elements in a fixed ratio.

Question 11

Which of the following is true about the chemical composition of the human body?

Accepted Answer

Four elements make up about 96% of the body’s weight.

Question 12

Which of the following best explains why water has a high resistance to temperature change?

Accepted Answer

Hydrogen bonds must be broken before water molecules can move faster, absorbing heat.

Question 13

Which of the following is a consequence of the release of $$CO_2$$ from factories in one region affecting coral reefs in another region?

Accepted Answer

Interactions within biological systems

Question 14

What is the role of buffers in biological systems?

Accepted Answer

Buffers minimize changes in pH.

Question 15

Which of the following is true about isotopes?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 16

Which property of water is most important for its role as the solvent of life?

Accepted Answer

Water is a polar molecule, allowing it to dissolve many substances.

Question 17

Which of the following best describes the difference between acids and bases?

Accepted Answer

Acids release $$H^+$$ ions, while bases accept and remove $$H^+$$ ions from solution.

Question 18

Which of the following is a real-world example of the importance of chemistry in biology?

Accepted Answer

The use of radioactive isotopes in radiometric dating to determine the age of fossils.

Question 19

Which of the following best explains why surface tension is higher in water than in most other liquids?

Accepted Answer

Hydrogen bonds between water molecules create strong cohesion at the surface.

Question 20

Which of the following is true about chemical reactions in cells?

Accepted Answer

Chemical reactions rearrange matter by breaking and forming chemical bonds.

Essential Chemistry for Biology: Chapter 2 Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드