AS paper 2

Question 1

how to write ionisation energy equations

Answer 1

element^n+ (g) –> Sr^(n+1)(g) + eˉ

e.g. Sr(g) –> Sr¹(g) + eˉ¹

Question 2

why ionisation decreases down the group

Answer 2

.more shells = + atomic radius and electron sheilding
.nuclear attraction decreases

Question 3

how to draw the experiment where you measure volume of H gas produced when group 2 metal reacts with water

Answer 3

.draw conical flask with water and metal chunks in it
.put a bong on the lip of the flask connected to a delivery tube conncected to a gas syringe

Question 4

why would a element with the same mass on group 2 but lower down produce less hydrogen

Answer 4

there would be less moles of the metal and so less moles of hydrogen gas formed

Question 5

why does Cl2 have a lower mp then P4

Answer 5

.P4 has more electrons
.so stronger london forces
.more energy needed to break LF

Question 6

what is the bonding and particles in metallic and gaint covalent structures

Answer 6

metal-
.metallic bonds
.cations(positive ions)
.delocalised electrons

covalent-
.covalent bonds
.between atoms

Question 7

difference between sigma and pi bond

Answer 7

sigma-
.direct overlap of orbitals
.bonding/electron density between atoms
.stronger

pi-
.sideways overlap of orbitals
.bonding/electron density is above and below atoms
.weaker

Question 8

alcohol + acid catalyst

Answer 8

alkene

OH and H form the C next to it gets removed and a double bond is formed between the 2 C

Question 9

how to draw the mechanism for HBr being added to an alkene

Answer 9

.H is delta positive and Br is delta negative
.arrow from double bond to H
.arrow from bond in HBr to Br(bond breaking)
.H attached to one either side of double bond

.arrow from lone pair on Br- to the other carbon+

Question 10

how to draw enthalpy profile diagram(activation energy)

Answer 10

.y-axsis = energy
.x axsis = progress reaction
.left line height to right line height = enthalpy change (ΔH)

Question 11

equation of NO radicals catalysing the break down of ozone

Answer 11

NO. + O3 –> O2 + NO2.
NO2. + O –> NO. + O2

Question 12

apparatus and method used to look at rate of reaction

Answer 12

.use beaker, balance and stop watch
.record mass at time intervals(give examples)

Question 13

equation for oxidisng a secondary alcohol

Answer 13

alcohol + [O] –> ketone(=o) + H2O

Question 14

why is using a beaker not suitable when oxidising alcohols

Answer 14

.it is very volatile, flammable and will evaporate away
.you should heat under reflux

Question 15

how to calculate percentage yelid

Answer 15

actual mass/expected mass x100

Question 16

how to identify a compound using infrared and mass spect

Answer 16

.find emprical formula by finding moles and diving by smallest num
.find molecular on mass spect by dividing furthest peak Mr by empirical Mr
.use infrared spect to look at functional groups

Question 17

ionic bond is

Answer 17

electrostatic attraction between positive ions and negative ions

Question 18

electrical conducitivites of solid and aqueous ionic compounds

Answer 18

soild-
.dont conduct as ions are fixed in lattice

aqueous-
.will conduct as ions are free in solution

Question 19

use of aqueous barium chloride

Answer 19

.acifided BaCl2 is used to test for sulfate ions
.positive = white precipitate
.Ba2+(aq) + SO42-(aq) –> BaSO4(s)

Question 20

what is barium nitride + water –>

Answer 20

barium hydroxide + ammonia

Ba3N2 + 6H2O —> Ba(OH)2 + NH3

Question 21

why might enthalpy change be different than the book value

Answer 21

.due to heat loss to surroundings
.incomplete reactions

Question 22

how to calculate formation enthalpy change ΔfH

Answer 22

.put the elements in their standard states at the bottom
.draw arrows upwards

Question 23

how to draw a diagram to show why something is soluble in water

Answer 23

.due to forming H-bonds NOF

.draw molecule
.draw delta nega on O and plus on H
.draw lone pairs on oxy
.draw a vertical dash line from H on compound to lone pair on oxygen on water molecule
.label hydrogen bond

Question 24

what does the end spike on a mass spect at the end represent

Answer 24

end = molecular ion

Question 25

how are aldehydes and carboxylic acids are formed

Answer 25

oxidising agent = K2Cr2O7 + H2SO4 and heat

.oxidising primary alcohol
.under distillation and forms aldehyde(H-C=O) and water
.under reflux and forms carboxylic acid(H-O-C=O) and water

primary alcohol + [O] –> aldehyde + water
primary alcohol + 2[O] –> carboxylic acid + water

Question 26

what is the condition for radical subsitution and overall equation

Answer 26

U.V. light