2 Lecture 1

Question 1

what is the definition of life

Answer 1

growth, reproduction

movement, response to stimuli, metabolism, catabolism, excretion…

Question 2

what do all living things need to be able to do

Answer 2

things change over time (growth)— if they are alive
ability to reproduce
ability to adapt
ability to use energy to do work and produce heat (homeostasis)
move something, change something, shift the shape of something,
whenever something uses energy it produces heat

Question 3

what is the cell theory

Answer 3

All living organisms are made of cells

Question 4

what are cells made of

Answer 4

What is everything made of?
Everything is made of Matter…
Matter is made of elements
Elements are made of atoms

Question 5

what are atoms made of

Answer 5

Atoms are made up of sub-atomic particles including protons, electrons & neutrons

Question 6

what are protons

Answer 6

Protons are positively charged & found in the nucleus of an atom

Question 7

what are electrons

Answer 7

Electrons are negatively charged & orbit the nucleus in energy shells – the number of electrons = the number of protons

Question 8

what are neutrons

Answer 8

Neutrons have no charge & are found in the nucleus, their number can vary

Question 9

do protons, electrons and neutrons have mass

Answer 9

Protons and neutrons have mass, but electrons do not have mass

Question 10

what is matter made of

Answer 10

elements

Question 11

what are elements

Answer 11

Element = chemically pure substance that cannot be broken down. Elements are made one type of atom

Question 12

Atoms of each element are characterized how

Answer 12

by a specific number of protons, electrons

Question 13

what is an atomic number

Answer 13

the number of protons

Question 14

what is an isotope

Answer 14

Isotopes of the same element have a different number of neutrons

Question 15

some isotopes are unstable, what does this mean

Answer 15

they are radioactive

Question 16

what kind of radiation is emitted from some isotopes

Answer 16

α (alpha), β (beta), or γ (gamma) radiation from the atomic nucleus

Question 17

Life on Earth can be characterized as what

Answer 17

carbon-based

Question 18

what is the basis of organic molecules

Answer 18

Carbon is the basis of the “organic molecules” that are associated with life

Question 19

what are the 2 types of molecules

Answer 19

organic and inorganic

Question 20

what does an organic molecule have to have

Answer 20

has a carbon backbone
at least 1 bond to hydrogen (H)
may also contain oxygen (O) &/or nitrogen (N)

Question 21

is carbon found in inorganic molecules

Answer 21

yes

Question 22

what are inorganic molecules

Answer 22

Lack carbon backbone & carbon-hydrogen bonds

Question 23

to understand chemical bonding, we need to do what

Answer 23

move past the “simple” Bohr model for electrons

Question 24

what is true for covalent bonds

Answer 24

1. A single covalent bond is made of 2 electrons
2. The 2 electrons are shared, i.e. one electron comes from each atom
3. Atoms can form bonds until their outermost (valence) shell is filled.
   1st shell: 2 e
2nd and 3rd shell: 8e

Question 25

what is the exception for covalent bonds

Answer 25

only exception is: Rare gases (noble gases) are inert— don’t form bonds because the outer (valence) shell is filled (aka they are already stable)

Question 26

what does it mean by Covalent bonds are very strong,

Answer 26

in that more energy is required to break the bond relative to other types of bonds

Question 27

A double covalent bond occurs when

Answer 27

atoms share two pairs of electrons

Question 28

covalent bonds are weak compared to

Answer 28

hydrogen bond

Question 29

hydrogen bond gives capacity to give very exchangeable but_________________

Answer 29

very strong couplings between molecules

Question 30

what are ionic bonds

Answer 30

opposite charges

Question 31

how ling do ionic bonds last for

Answer 31

long lives

Question 32

what makes ionic bonds so great

Answer 32

ionic binds are long lives, but are part of what makes water such a great environment for life— it acts as a solvent that allows atoms to freely exchange

Question 33

are hydrogen bonds strong on their own

Answer 33

no, only when there are a lot together

Question 34

what is van der waals interactions—

Answer 34

can be both attractive and repulsive

Question 35

what is predictable of covalent bonds

Answer 35

Each covalent bond has a predictable length and angle, which makes it possible to predict the three-dimensional structures of molecules

Question 36

what are the rules of covalent bonds

Answer 36

1. A single covalent bond is made of 2 electrons
2. The 2 electrons are shared, i.e. one electron comes from each atom
3. Atoms can form bonds until their outermost (valence) shell is filled
   Rare gases are inert don’t form bonds because the outer (valence) shell is filled

Question 37

what are the types of covalent bonds

Answer 37

ionic, hydrogen and just covalent (i think)

Question 38

are e- always shared equally between covalent bonded atoms

Answer 38

Electrons are not always shared equally between covalently bonded atoms

Question 39

what is electronegativity

Answer 39

The attractive force that an atom exerts on electrons is called electronegativity

or

the tendency of an atom to attract electrons when it occurs as part of a compound

Question 40

Ionic bonds form by how

Answer 40

electrical attraction

aka steals e-

Question 41

which atom attracts the e-

Answer 41

the more electronegative (en) atom attracts electrons

Question 42

do ionic bonds last long

Answer 42

does not last long… taking something away from something, and as a result the 2 atoms become happier but they are still interacting, so the bond can be easily broken

Question 43

microscopic interactions are based on what

Answer 43

random collisions

Question 44

what state can water list in

Answer 44

water can exist as a solid, a liquid or as a gas

Question 45

as a liquid, the H-bonds between H2O molecules do what

Answer 45

as a liquid, the H-bonds between H2O molecules break continuously but randomly- gives fluidity & surface tension