Chapter 2: The Chemical Basis of Life

Question 1

What are the typically referenced main elements

Answer 1

CHNOPS, carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur

Question 2

What is matter?

Answer 2

Anything that occupies space and has mass. It makes up living organisms and is made up of elements

Question 3

What are elements?

Answer 3

Substances that cannot be broken sown to other substances by ordinary means. Each element has a symbol, and there are 92 elements found in nature.

Question 4

What do 96% of living organisms consist of?

Answer 4

oxygen, carbon, hydrogen, nitrogen

Question 5

What does the other 4% of living organisms consist of?

Answer 5

Calcium, phosphorus, potassium, sulfurr, sodium, chlorine, and magnesium

Question 6

What are trace elements?

Answer 6

Elements that are only needed for life in very small quantities but are still necessary

Question 7

Compound

Answer 7

substance containing 2+ elements in a fixed ratio;

Question 8

Atoms

Answer 8

the smallest unit of matter that retains the properties of a given element

Question 9

subatomic particles

Answer 9

smaller than an atom, protons and neutrons found in atom’s nucleus, electrons orbit nucleus in electron cloud since the speed of electrons is nearly the speed of light

Question 10

electron arrangement

Answer 10

the farther an electron is from the nucleus, the greater its energy. electrons occur in electron shells (1, 2, or more). The innermost shells fill up with only 2 electrons, outermost shells of most main elements of life can hold 8 electrons or 4 pairs

Question 11

Filling the outermost electron shell

Answer 11

Elements that do not have outer shell filled readily react with other elements to fill those shells. chemical bonds take place when atoms share/donate/receive other electrons, and so stay close together held by attraction

Question 12

Octet Rule

Answer 12

says that atoms tend to gain, lose, or share their electrons so as to have 8 electrons in outer electron shell

Question 13

Name parts of an atom and charges

Answer 13

nucleus- protons (+) and neutrons (no charge)

electrons(-) are in the surrounding electron cloud

Question 14

name 2 key trace elements discussed and their importance

Answer 14

iron is necessary for energy processing and transporting oxygen in blood, need it so you don’t get anemia

iodine is essential ingredient of a hormone produced by thyroid gland

Question 15

why does bonding take place?

Answer 15

because the goal of each atom is to have a full outer shell, in most cases 8 electrons, otherwise known as octet rule (except for H and He which only need 2)

Question 16

what’s the difference between polar and non polar bonds?

Answer 16

non polar bonds are shared equally and polar bonds are not

Question 17

what is the difference between cohesion and adhesion?

Answer 17

cohesion is anything sticking to more of its same kind, adhesion is two different kinds of things sticking to one another

Question 18

what is the difference between a solvent and a solute?

Answer 18

A solute will always dissolve in the solvent

Question 19

xylem vs phloem

Answer 19

xylem transfers minerals and waters, and phloem transfers organic materials

Question 20

what is acid on a pH scale

Answer 20

0 to anything below 7

Question 21

what is neutral on ph scale

Answer 21

7

Question 22

what is basic on pH scale

Answer 22

anything above 7 to 14

Question 23

what does likes dissolve likes mean

Answer 23

polar molecules will dissolve polar molecules, non-polar dissolves non-polar, non-polar and polar do not dissolve

Question 24

In terms of the donation or the acceptance of protons, please compare and contrast acids and bases.

Answer 24

Acids donate Hydrogen ions (protons) to a solution whereas bases are proton acceptors

Question 25

Why are acids called proton donors?

Answer 25

They contribute additional H+ ions to a solution when dissolved/dissociated (in water). A Hydrogen atom with a +1 charge has no electrons, so it is essentially just a proton