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

$$\text{Mass number} = \text{Atomic number} + \text{Number of neutrons}$$

Question 1

Which process allows sunflower plants to absorb and detoxify heavy metals from contaminated soils, as used after Hurricane Katrina and in Australia?

Accepted Answer

Phytoremediation

Question 2

Which subatomic particle determines the atomic number of an element?

Accepted Answer

Proton

Question 3

A radioactive isotope of carbon, $$^{14}C$$, is used in dating fossils. What makes it different from $$^{12}C$$?

Accepted Answer

It has more neutrons

Question 4

Which equation correctly represents the photosynthesis reaction?

Accepted Answer

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

Question 5

Which property of water allows a spider to walk on its surface, as shown in the image?

Accepted Answer

Surface tension

Question 6

What is the main reason ice floats on water?

Accepted Answer

Hydrogen bonds in ice are more ordered, making it less dense

Question 7

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

Accepted Answer

Polar covalent bond

Question 8

What is the trend of electronegativity across the periodic table?

Accepted Answer

It increases from bottom to top and left to right

Question 9

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

Accepted Answer

A substance that minimizes changes in H+ or OH- concentrations

Question 10

If a solution has a pH of 5, which statement is true?

Accepted Answer

It is acidic and has a high concentration of H+

Question 11

Which property of water is most important for the transport of water and nutrients against gravity in plants?

Accepted Answer

Cohesion and adhesion due to hydrogen bonding

Question 12

What is the difference between a cation and an anion?

Accepted Answer

A cation has lost an electron; an anion has gained an electron

Question 13

Which equation correctly represents the relationship between mass number, atomic number, and neutrons?

Accepted Answer

$$	ext{Mass number} = 	ext{Atomic number} + 	ext{Number of neutrons}$$

Question 14

Which of the following is an example of a weak chemical interaction that is crucial for the functional form of large biological molecules?

Accepted Answer

Van der Waals interaction

Question 15

Why are oil molecules hydrophobic?

Accepted Answer

They have many nonpolar covalent bonds

Question 16

A gecko can walk on walls due to which type of interaction?

Accepted Answer

Van der Waals interactions

Question 17

Which of the following is NOT a property of water important for life?

Accepted Answer

High density as a solid

Question 18

What happens when acids and bases are mixed together in water?

Accepted Answer

They neutralize each other, forming water

Question 19

Which term describes a substance that has an affinity for water?

Accepted Answer

Hydrophilic

Question 20

Which of the following best explains why coastal cities like Los Angeles have milder temperatures compared to inland cities like Palm Springs?

Accepted Answer

Water absorbs and releases heat slowly, moderating temperature

Chapter 2: The Chemical Context of Life – Study Notes

Study Guide - Practice Questions