Chapter 1: Atoms and Molecules

Question 1

Define: Matter

Answer 1

Any substance that occupies space and has mass.

Question 2

Define: Element

Answer 2

Matter of one type that can’t be created or broken down by ordinary chemical means.

Question 3

Define: Compound

Answer 3

Combination of 2 or more elements bonded together.

Ex: H2O, CO2

Question 4

Define: Molecule

Answer 4

Two or more atoms covalently bonded together (atoms share electrons).

Ex: O2, CO2

Question 5

Important note about CO2 and O2

Answer 5

CO2 is a molecule and a compound, but O2 is ONLY a molecule.

Question 6

What is CO2 classified as?

Answer 6

A compound

Question 7

Oxygen (O2) can be classified as a what?

Answer 7

Molecule

Question 8

Oxygen (O) is classified as a what?

Answer 8

Atom

Question 9

Define: Inorganic Compound

Answer 9

A compound that does not contain both carbon and hydrogen.

Ex: H2O (because it doesn’t have one oxygen atom)

Question 10

Define: Organic Compound

Answer 10

Compound that contains both Carbon and Hydrogen.

Ex: Glucose (C6H12O6).

Question 11

Carbon atoms point

Answer 11

Carbon atoms = structural backbones of many large, complex organic molecules in the body.

Question 12

What happens when you break covalent bonds?

Answer 12

• You release energy.

Energy released from ATP –> Energy for cellular work + ADP + Pi (Phosphate group)

• Energy from metabolism of food combines with ADP + Pi to re-create ATP

Question 13

List the 3 subatomic particles

Answer 13

1. Protons
2. Neutrons
3. Electrons

Question 14

Define: proton

Answer 14

A heavy subatomic particle having a (+) charge and found in the atom’s nucleus

Question 15

Define: Neutron

Answer 15

A heavy subatomic particle having no electrical charge and found in the atom’s nucleus

Question 16

Define: Electron

Answer 16

A subatomic particle having a negative charge and nearly no mass.

• Found orbiting atom’s nucleus.

Question 17

Define: Atomic Number

Answer 17

The number of protons in an element.

Question 18

Define: Mass Number

Answer 18

The sum of protons and neutrons of an element.

Question 19

What is the formation and breakage of substances in the body due to?

Answer 19

Electrons participating in reactions.

• Electrons tend to stay within certain regions (Shells)

Question 20

Electron shells notes

Answer 20

• All electron shells are considered complete with eight electrons.
• Complete valence shell makes an atom non-reactive.
• Carbon very reactive, cause 4/8 valence shells there. Tries to form 2 extra bonds to fill the shell up.

Question 21

Define: Valence Shell

Answer 21

The outermost shell or orbit of an atom.

Question 22

Define: ions

Answer 22

Atoms that donate or accept electrons in order to have a full valance shell.

Question 23

Define: Cation

Answer 23

When an atom donates electron(s) generating an ion with a positive charge.

Question 24

Define: Anion

Answer 24

When an atom accepts electrons, leading to an ion with a negative charge.

Question 25

Define: Ionic Bond

Answer 25

a chemical bond formed when one atom gives up one or more electrons to another atom.

Question 26

Define: Covalent Bond

Answer 26

When electrons in outermost valence shell are shared to fill valence shells of both atoms involved.

Ex: O2, CO2.

Question 27

Define: Nonpolar Covalent Bond

Answer 27

A bond where there is a balanced, equal sharing of electrons.

Question 28

Define: Polar Covalent Bonds

Answer 28

An unbalanced, unequal sharing of electrons.

• Results in regions of a molecule having opposite partial charges (dipole).

Ex: H2O. H-bond slightly (+), O bond slightly (-).

Question 29

Define: Hydrogen Bond

Answer 29

A weakly positive hydrogen atom that binds to an electronegative atom from another molecule.

Question 30

Define: Dipole-Ion Bond

Answer 30

When the partial charges on water pull something (ex: NaCl) apart.

• Weakly (+) portion of water attracts Cl- and negative parts of water attract Na+.

Question 31

What do dipole charges repel?

Answer 31

Nonpolar covalent bonds.

• Partial charges on water repel nonpolar molecules like fats, lipids, and oils.

Question 32

Define: Dipole

Answer 32

A bond or molecule whose ends have opposite charges.