water & carbon

Question 1

what is the orbital

Answer 1

location where an electron may be found a vast majority of the time

Question 2

where are the electrons in the first row of the periodic table found

Answer 2

in a sphere in the atomic nucleus

Question 3

how many orbitals do the second row of elements in the periodic table have and what are they

Answer 3

4 orbitals - spherical, 2py, 2px, 2pz

Question 4

what happens to the orbitals when electrons are shared

Answer 4

they hybridize - form a tetrahedron (new shape) e.g. methane / ethane

Question 5

how many degrees away from eachother are all 4 orbitals of a tetrahedron (bond angle of tetrahedron)

Answer 5

109.5

Question 6

Bond angle of water

Answer 6

104.5 degrees - two lone pairs of electrons in oxygen push away from eachother, opening the angle

Question 7

what kind of molecule is water

Answer 7

polar - unequal sharing of its electrons - oxygen strongly pulls all the electrons

Question 8

what is gas

Answer 8

single molecules of water bind and are liberated from one another with additional energy

Question 9

what is liquid

Answer 9

fragile disorganised hydrogen bond – last few trillionths of a second

Question 10

what is solid

Answer 10

4 neighbors in 3d states – makes H-bonds more spaced out – less dense than liquid so it floats (expansion upon freezing)

Question 11

6 emergent properties of water

Answer 11

• Cohesion, adhesion + surface tension (allows paper clips to float etc)
• Moderates temperature
• Evaporative cooling
• Expansion upon freezing
• Universal solvent for life
• Acid base chemistry

Question 12

what does the water property cohesion mean

Answer 12

H-bonds holding water together – sticks to itself e.g. travels up trees

Question 13

what does the water property adhesive mean

Answer 13

H-bonds holding water to polar or charged things e.g. why oils and water don’t mix – methane = non-polar

Question 14

what does the water property moderates temperature mean

Answer 14

water absorbs heat from warmer air and releases to cooler air

Question 15

High specific heat meaning

Answer 15

amount of heat that must be absorbed or lost to change temp by 1°c (takes lots of heat to break lots of hydrogen bonds) - basis for the metric system

Question 16

calorie meaning

Answer 16

amount of energy for 1 gram of water to be raised by 1°c

Question 17

what does the water property evaporative cooling mean

Answer 17

transfer from liquid -> gas to cool the system

Question 18

High heat of vaporization meaning

Answer 18

amount of heat required for 1g of a substance to be raised by 1°c

Question 19

what does the water property Universal solvent for life mean

Answer 19

water forms hydration shells around other polar or charged molecules e.g. the H+ in water will attract the Cl- in salt, O- will attract the Na+

Question 20

what’s hydrophilic

Answer 20

polar or charged things – affinity for water (watery)

Question 21

what’s hydrophobic

Answer 21

nonpolar or noncharged – no affinity to water (oily) - PHOBIA OF WATER

Question 22

what is pH

Answer 22

number of H+ ions in a solution

Question 23

what does it mean when Proton number is higher in a solution

Answer 23

acidic (things that put protons into solution)

Question 24

what does it mean when Proton number is lower in a solution

Answer 24

bases

Question 25

what rarely happens when H2O + H2O

Answer 25

= H3O + OH
(hydronium + hydroxide)

Question 26

what mostly happens when H3O + OH

Answer 26

= H2O + H2O

Question 27

hydronium symbol

Answer 27

H3O (+)

Question 28

hydroxide symbol

Answer 28

OH (-)

Question 29

what happens when H3O x OH

Answer 29

10 (-14)
- pH follows after the number of hydronium e.g.
10(-7) x 10(-7) = pH 7
10(-11) x 10(-3) = pH 11

Question 30

how does carbon enter the biosphere

Answer 30

as CO2

Question 31

what is carbon unique in its ability to do

Answer 31

to form large diverse molecules – perfect sharer for building things (creates backbones)
- Forms bands with HNOPS to make a variety of molecules

Question 32

important thing to remember about carbon

Answer 32

PERFECT SHARER

Question 33

what’s the study of carbon called

Answer 33

organic chemistry

Question 34

what shape is Carbon linked by double bond (C = C)

Answer 34

trigonal planer e.g. ethene (ethylene)

Question 35

trigonal planer bond angles

Answer 35

120 degrees

Question 36

Things that can be added to hydrocarbon backbone

Answer 36

OH hydroxyl
C=O carbonyl
COOH carboxyl
NH2 amino
PO4 phosphate
S-H sulfhydryl
CH3 methyl

Question 37

what properties emerge by adding hydroxyl group to hydrocarbon backbone

Answer 37

gives polar characteristic due to oxygen – WATER SOLUBLE

Question 38

what properties emerge by adding carbonyl group to hydrocarbon backbone

Answer 38

gives polar characteristic due to oxygen – WATER SOLUBLE

Question 39

what properties emerge by adding carboxyl group to hydrocarbon backbone

Answer 39

gives an acidic characteristic - donates H+

Question 40

what properties emerge by adding amino group to hydrocarbon backbone

Answer 40

gives basic characteristic – can take on a proton

Question 41

what properties emerge by adding Phosphate group to hydrocarbon backbone

Answer 41

• gives extra acidic characteristic by donating H+
• increased polarity

Question 42

what properties emerge by adding sulfhydryl group to hydrocarbon backbone

Answer 42

• makes disulfides
• moderates polarity - no oxygen

Question 43

what properties emerge by adding methyl group to hydrocarbon backbone

Answer 43

• nonpolar - no oxygen - hydrophobic