p block

Question 1

what does “maximum 4 covalent bonds” mean

Answer 1

2nd period are restricted to 2s and 2p, 3rd or heavier have d orbitals available, can form more than 4 bonds, weaker bond, EA increased

Question 2

presence of oxygen and alkali metals

Answer 2

cations (M+) in combination with:
O^2- (oxide), O2^2- (peroxide), or O2^- (superoxide)
*atoms prefer to find ox atom that matches in size

Question 3

what does “greater prosperity for multiple bonds” mean

Answer 3

for multiple bonds, pi overlap of p orbitals must be effective, this is more likely to happen on a pair of 2p orbitals than diffuse 3p (larger) atoms, therefore the 3p have lower higher EA, lower IE, weaker

Question 4

boron properties

Answer 4

g13, metalloid with covalent network structure, hard, black, high melting point

Question 5

aluminium properties

Answer 5

g13, typical metal, moderate melting point (represents elements), extended structure

Question 6

trend of ionic radius in G13

Answer 6

has a 3d subshell, electrons are more poorly shielded, higher Zeff, radius decreases

Question 7

common oxidation states for G13

Answer 7

most common is +3, going down a group, +1 becomes possible for Ga, In, and Ti, due to inert pair effect (reluctancy to participate in bonding)

Question 8

natural sources of boron

Answer 8

borate minerals, extracted through reduction, ox state of 3+,

Question 9

industrial applications of boron

Answer 9

boric acid: white solid, disinfectant, insecticide, fiberglass
boron: resistant to thermal shock, cookware, lab glass

Question 10

industrial application of aluminium

Answer 10

most abundant in earths crust, can be extracted 2 ways
reduction: required melting at high temperatures
hall-heroult: addition of cryolite, lowered melting point

Question 11

applications of aluminium

Answer 11

strong, lightweight alloy, resistant to corrosion when anodized, can be recycled, valuable for transportation, construction, consumer packaging

Question 12

G15 element properties

Answer 12

pnictogens, attain states from -3>+5
going down a group neg ox state becomes less stable, +3 becomes only common for B

Question 13

nitrogen properties + applications

Answer 13

80% of atmosphere, filtrated, fractional distillation, highly unreactive, good for packaging food, manufacturing electronic decies, science experiment, used as cryogen to store temperature sensitive materials

Question 14

phosphorous properties + applications

Answer 14

most important allotropes: white and red
phosphate minerals, used as fertilier, extracted through reduction

Question 15

white phosphorous

Answer 15

white, waxy, highly toxic, low MP
tetrahedral p4 clusters, bond angle 60º (strained), highly reactive, nonpolar, ignites on contact with air, stored underwater

Question 16

red phosphorous

Answer 16

red, nontoxic, high melting point
polymeric chains, not strained, less reactive, illegal manufacturing meth, striking surface of match boxes

Question 17

ammonia (nh3)

Answer 17

colourless gas, forms weak base
prepare through haber process, fertilizer

Question 18

phosphine

Answer 18

cph3, colourless, highly toxic gas, no bronsted lowry basic properties but can act as lewis base, rat poison,

Question 19

dinitrogen monoxide

Answer 19

colourless, sweet smelling gas, dental anesthetic or rec drug, aerosol for whipped cream

Question 20

nitrogen monoxide

Answer 20

colourless gas, reacts with ox at high temps in car engines or lightning, important for neural transmissions

Question 21

nitrogen dioxide

Answer 21

orange-brown toxic gas, produced fron NO due to radical reactions with O2 in atmosphere, leads to NO3-, excess produced from car engines, leads to pollution

Question 22

tetraphosphorus hexaoxide

Answer 22

white, waxy solid, forms when P reacts with limited oxygen, tetrahedral arrangement of P atoms with 6 bridging atoms

Question 23

tetraphosphorus decaoxide

Answer 23

white solid, , reacts with excess oxyge, tetrahedral with 6 bridging and 4 terminal O

Question 24

nitrous acid

Answer 24

weak acid, +3 ox state, useful reagent in organic solutions

Question 25

nitric acid

Answer 25

strong acid, ox state +5, ostwald process: oxidation of ammonia followed by disproportionate reactions, major application with ammonia for ammonia nitrate (fertilizer)

Question 26

phosphorus acid

Answer 26

weak acid, +3 ox state, diprotic

Question 27

phosphoric acid

Answer 27

weak acid, +5 ox state, triprotic acid, starting material for fertilizers

Question 28

G16 elements

Answer 28

calgogens, ox state from -2,+6, positivef is more stable down the group, industry in semiconductors

Question 29

dioxygen, O2

Answer 29

normal, colourless gas, low BP, 21% of atmosphere, paramagnetic

Question 30

ozone (trioxygen)

Answer 30

pungent, diamagnetic, low BP, pale blue, low concentrations in upper atmosphere, low atmosphere is considered pollution

Question 31

sulfur

Answer 31

more allotropes than any other element, tendency to form bonds to itself

Question 32

yellow sulfur

Answer 32

stable at room temp, yellow, cyclic 8 crown shape, deposits of earths crust or minerals, fossil duels are contaminated (removed to avoid combustion), oxidized to O3 which can combine with moisture to form acid rain, major application is sulfuric acid, most important in industry (used as strong acid) (strong dehydrating agent)