Lecture One: Introduction Flashcards
(108 cards)
1
Q
How much of the world is water
A
71%
2
Q
what are the 3 phases of water?
A
liquid, vapour, and solid
3
Q
what compound is in 3 phases?
A
water is the only one naturally able to reside in 3 phases.
4
Q
How did water come to earth , theory?
A
ice is on astroids, physicists think the earth was bombarded with astroids and mediators , this then melted on impact and created water on earth
5
Q
what does an atom consist of?
A
nucleus, electron shell (cloud)
6
Q
what is in the nucleus?
A
contains: protons (positive charge)
neutrons (no charge)
7
Q
what does the electron shell contain?
A
Electron shell has electrons (negative charge)
8
Q
electrons have what charge?
A
negative charge
9
Q
protons have what charge?
A
positive
10
Q
Do neutrons have a charge?
A
no
11
Q
what is H?
A
hydrogen
12
Q
what is O and C?
A
Oxygen and Carbon
13
Q
whats an ion?
A
an atom or molecule that has a net electric charge, which has been made due to the gain or loss of an electron
14
Q
can you gain and loose protons?
A
no never
15
Q
which electrons are gained and lost?
A
ones in the outer most cell
16
Q
whats Na+ ?
A
Sodium
17
Q
whats Cl- ?
A
chloride
18
Q
why does sodium have a positive charge?
A
?
19
Q
whats explosive when exposed to water?
A
sodium
20
Q
chlorine gas can do what to you?
A
kill you
21
Q
sodium and chlorine make?
A
salt
22
Q
what is S ?
A
sulphur
23
Q
what is P?
A
phosphorus
24
Q
whats K?
A
potassium
25
what happened in 1953?
basic form of DNA was being discovered
26
what happens in 2003?
mapping the human genome
27
whats the atomic number?
number of protons in the nucleus of an atom
28
Are noble gases reactive?
no
29
why are atoms allowed to ionise?
because of the atoms in the outer shell
30
what are the 3 types of bonds we need to know?
covalent, ionic, hydrogen bonds (weak)
31
covalent bonds involves what?
the sharing of electrons
32
In ionic bonding what happens?
one atom gain an electron, one atom uses an electron
33
what is eltrostatic attarction?
?
34
what do weak interactions do?
help stick molecules together
35
whats a common weak interaction?
hydrogen bonds
36
how long does a hydrogen bond last?
1 nano second
37
whats the relative strength of all bonds?
covalent is stronger then ionic, ionic is stronger then hydrogen
38
what the hardest bond to break?
covalent
39
when breaking a bond whats released?
energy
40
what are molecules made up of?
atoms
41
is water an ionic molecule?
no
42
what type of molecule is water?
a polar molecule
43
whats a polar molecule?
when one side is positively charged and one is negatively charged
44
what makes water have odd properties?
the fact that its a polar molecule
45
if water wasn't polar what would happen to ice?
would melt really easily
46
in water hydrogen is slightly ____ and oxygen is ____
1. positive
| 2. negative
47
dotted line represents what bond?
hydrogen bonds
48
Hydorgen bonds form an break how many times a second
a billion times
49
what allows water to be liquid on earth?
the hydrogen bonds found in its structure
50
what gives water its heat capacity?
?
51
water takes ___ to heat and ___ to cool
1. long
| 2. long
52
ice is a ____ energy state then liquid water
1. lower
53
Hydrogen bonds are stronger or weaker at a lower temperature?
stronger
54
atoms and molecules have ___ activity at higher temperatures
1. more
55
whats the boiling point of water?
100c
56
whats the freezing point of water?
0c
57
what happens to water when it freezes (heat of fusion)?
when water freezes its releases heat
58
what happens when ice melts?
water is absorbing heat
59
what powers hurricanes and thunderstorms?
heat vaporisation
60
heat is absorbed when?
when water goes from liquid to vapour
61
are heat and temperature the same?
no
62
what is heat?
the total energy of molecular motion
63
what is temperature?
measure of the average energy
64
what happens when water changes phases?
there is a transfer of heat
65
does water have a high heat capacity?
yes
66
whats the ratio for water/air?
4/1 , 4 times as much energy to change water temperature by 1 degree compared to air temperature
67
what the ratio for water/ethanol ?
2/1 , 2 times as much energy to change water temperature by 1 degree compared to ethanol temperature
68
what stores more heat, water or air?
water stores more heat
69
what do bois in Maine gulf measure?
water temperature
70
what temperature does salt water freeze at and why?
salt water freezes at -1.86c due to ions
71
why can water dissolve salt?
the covalent bonds of water are stronger than the ionic bonds in the salt molecules
72
what does water do to salt?
Water molecules pull the sodium and chloride ions apart, breaking the ionic bond that held them together.
73
can water dissolve non polar molecules?
no (eg no lipids fats)
74
calcium carbonate dissolves very ____.
1. slowly
75
what won't dissolve?
ion oxide
76
in clear water what light penetrates the deepest ?
blue light
77
what light penetrates water the least?
red light
78
how far does uv light penetrate water?
200 m
79
what penetrates water further blue light or uv?
uv
80
what percent of light energy penetrates to 100m?
less then 1%
81
what is turbid?
tired up water, with particulate matter
82
what happens to light in turbid waters?
65% of light is absorbed in first 100m
83
what is ph?
measure of acid and alkaline
84
human saliva is?
neutral
85
neutral ph is ?
7 and above
86
ph scale is?
logarythmic
87
what are the major sources of salt in sea water?
6 ions, sodium, magnesium, calcium, potassium, chloride and sulfate
88
sea water is measured in what?
parts per thousand
89
what ion is in water at the highest amount?
chloride
90
sea water averages at how many parts per thousand?
35 parts per thousand
91
what reduces sea water acidity?
fresh water from river
92
what does fishing do to sea water?
removes salt
93
what gases are found in sea water?
nitrogen, oxygen, carbon dioxide + others
94
what is oxygen a bi product of?
photosynthesis
95
what is solubility?
ability for a product to dissolve in a solution
96
carbon dioxide travels from where?
ocean to atmosphere
97
what requires calcium carbonate?
corals,
98
sea water is saturated with?
carbonate
99
what happens if the pH is low?
its hard to precipitate out calcium carbonate
100
where does carbon get released from?
carbon cycle is important, released from organisms through respiration.
101
carbon is also found from?
dead organisms
102
carbon is found in shells corals and ?
skeletons in organisms that have them
103
whats density measured in?
g/cm^3
104
whats the density of fresh water?
1
105
whats the density of salt water?
1.027
106
As temperature decreases what happens to density?
density increases
107
colder water is more or less dense?
more
108
as solidity increases what happens to density?
it also increases
