2. (a) (i) Atomic number: number of protons ( in the nucleus) (1) Mass number: [Total/sum of the)numbers of protons plus/and neutrons (1) 2

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Joshua Lane
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1 1. (a) 36.5/23 = /32 = /16 =2.38 (1) 1.59/0.79 = /0.79 = /0.79 =3.01 (1) Na 2 SO 3 (1) 3 (b) (i) /1000 = (1) 1 (ii) 300/24 000(1) = (1) (iii) moles has a mass of 0.800g 1 mol = 0.800/ = 64 (2) 2 (there are other valid ways of carrying out this part of the calculation) Note ; part (iii) is consequential on part (ii) but max 1 if the final answer so produced is not sensible e.g. a molar mass of 0.64) (iv) flame test (1) yellow / ange colour (1) 2 (c) (i) S (1) 1 (ii) 32S16O 2 (1) positive (1) 2 (d) Na 2 SO 3 + 2Cl 2NaCl + SO O ( 2NaCl + 2 SO 3 ) all crect products (1) balanced (1) 2 2. (a) (i) Atomic number: number of protons ( in the nucleus) (1) Mass number: [Total/sum of the)numbers of protons plus/and neutrons (1) 2 (ii) Na Na+ a sodium ion 1 (b) (i) ( 79Br81Br )+ ( 79 Br 81 Br )+ 1 (ii) Some wking justification (1) 50:50 equivalent (1) 2 e.g. Because the two peaks at 158 and 162 are the same height (1) the relative abundance of each must be 50%(1) (c) The heat /energy/ enthalpy change/ released per mole of electrons (1) f addition to 1mol of gaseous(bromine) atoms (1) Br(g) + e Br (g) (1) 3 The wd gaseous may be omitted provided the state symbol is present on both sides of the equation / vice versa [14] NT Exampro 1

2 (d) (i) The heat /energy/ enthalpy change/needed per mol of electrons (1) f removal from 1mol of gaseous(neon) atoms (1) The equation is not asked f but can be used to sce the second mark above. 2 Ne(g) e Ne+(g) (ii) (The first ionisation energy increases as) the nuclear charge increases (1) (Inner shell) shielding remains the same (as nuclear charge increases)/ electrons removed from same energy level/shell (1) 2 (iii) there is less inner shell shielding in Ne (1) Although there is an increase in the nuclear charge from Ne to Ar (1) OR atomic radius f Ne is smaller than f Ar/ the outer (2p) electron in Ne is closer to the nucleus than the (3p) electron in Ar (1) 2 3. (a) (i) electron configuration 3d64s2 4s2 number of outer electrons 1 (ii) 26 protons, 26 electrons, 30 neutrons all 3 (2) any 2 (1) 2 (iii) atoms (of same element) with same number of protons same atomic number 1 different number of neutrons mass number 1 (b) (i) A ionisation not vapisation 1 B acceleration 1 C deflection 1 D detection 1 (ii) (5.8 54) + ( ) + (2.2 57) + ( ) = (a) (i) Fast/high energy/fired/bombard/electrons (electron gun) strike sample atoms Knocking out/ remove electron from sample atom 2 (ii) Electric field/charged plates/negative plates 1 (b) (i) 65Cu+ 1 (ii) (2)(different) isotopes 1 (iii) ( ) + ( ) divided by ( ) (1) = 63.6/63.62/ (1) 2 [15] [11] [7] NT Exampro 2

3 5. (a) (i) C C C CN C C C CN (ii) C C C N C C C N Br C 3 C 2 C 2 N 2 C 3 C 2 C 2 N 3 +Br- Allow secondary, tertiary quarternary amine 1 (b) PCl 5 (1) Steamy / white/ misty fumes / valid test f Cl shows alcohol (1) acidified potassium dichromate (1) goes ange to green shows alcohol (1) acidified potassium manganate(vii) (1) goes from purple to colourless / decolises shows alcohol (1) could be in alkali when colour will be green brown any other plausible test to show presence of chlo group e.g hydrolysis with NaO and acidify (1) add silver nitrate solution and result (1) 2 (c) (i) Methylpropan 2 ol C C 3 C C C C C C O 3 3 (ii) Acidified potassium dichromate / in dilute sulphuric acid / 2 SO 4 (1) warm (1) ange solution green with butan-2-ol (1) no change with 3o alcohol (1) O iodofm test add iodine and NaO KI and NaClO (1) stand warm (1) cream/ yellow ppt (1) only with butan 2 ol (1) 1 NT Exampro 3

4 Acidified alkaline potassium manganate(vii) (1) warm (1) purple colour goes colourless green / brown (1) only f butan 2 ol (1) 4 (iii) Butan 2 ol gives ketone / easily oxidised to the ketone (1) Methylpropan-2-ol not easily oxidised (1) in the iodofm test identify the ppt as CI 3 (1) explain that this needs C 3 C O group to be present (1) 2 6. (a) (i) To neutralise (potassium hydroxide) / to make sure the solution is acidic (as this is needed f test) (1) Otherwise silver nitrate reacts with alkali / prevent fmation of other ppts / remove anions that could react with the silver nitrate (1) 2 (ii) Cream / off white / pale yellow / buff (1) AgBr (1) 2 (iii) Precipitate dissolves / (colourless) solution fmed / ppt disappears (1) 1 (b) Reagent (1) PCl 5 / K 2 Cr 2 O SO 4 / KMnO SO 4 / Na / SOCl 2 Observation (1) must relate to reagent chosen Fmulae (1) may relate to product from the reagent the ganic compound PCl 5 (1) White/steamy/misty fumes/vapour/gas (1) Cl / chlo derivative (C 4 9 Cl) / POCl 3 (1) K 2 Cr 2 O SO 4 Orange to green solution C 3 C 2 COC 3 / Cr 2 (SO 4 ) 3 / K 2 SO 4 / 2 O KMnO SO 4 Purple to colourless solution C 3 C 2 COC 3 / MnSO 4 / K 2 SO 4 / 2 O Na Bubbling C 4 9 ONa / 2 3 [11] [8] 7. (a) (i) N = 6.25 = (1) N 2 (1) (3) (ii) The mass spectrum of this compound shows a molecular ion peak a m/e of 32.Thus Relative Molar Mass = 32 n (N + 2) = 32 NT Exampro 4

5 n 1(14 + 2) = 32 n = 2 Molecular fmula = 2 N 2 = N 2 4 (1) (1) 4 (b) (i) N 3 + N 2 Cl+ NaO N NaCl + 2 O (1 mark f reactants side -1mark f product side of equation) (2) (ii) 1 mole of hydrazine produced from 2 moles of ammonia gas(1) 32 g of hydrazine produced from 2 24 dm³ of ammonia gas (1) g of hydrazine produced from 2 dm³ of ammonia gas 32 = 3 dm³ (1) (3) 5 8. (a) (i) Valid diagram 4 carbons overall C 4 10 (2) (b) (c) (d) (ii) Valid diagram 4 carbons C = C (2) 4 Valid chline substituted product f the structure given in (a) Cl (2) 2 Any chline addition product f the structure given in (b) Crectly drawn (2) 2 Bromine solution added to unknown Red/ange colour of bromine Goes colourless (3) 3 (e) (i) Repeating unit of C 2 No double bonds shown (2) (ii) Electrophilic addition (1) (iii) Any valid use e.g. packaging, containers, electrical insulation, piping, guttering. Any other valid use (1) 4 9. ACCEPT crect names fully crect fmulae f all reagents Alkene Reagent: Aqueous bromine / bromine in a suitable solvent potassium manganate(vii) + sulphuric acid / acidified / potassium manganate(vii) + sodium hydroxide / alkaline (1) Observation Bromine: ange / brown / yellow colourless / decolourised KMnO 4 in acid: purple colourless / decolourised KMnO 4 in alkali: purple green (solution) / brown ppt (1) Max 2 [9] [15] NT Exampro 5

6 Alcohol Chloalkane Alkane Reagent: PCl 5 / phosphus pentachlide Na / sodium (1) Observation PCl 5 : steamy / misty fumes / gas which turns damp blue litmus red / fms dense white fumes with N 3 / gives white ppt with AgNO 3 Na: effervescence OR positive test f 2 (1) Do NOT allow any oxidation reaction Max 2 Reagent: aqueous sodium hydroxide (1) followed by Nitric acid + silver nitrate (1) OR Aqueous silver nitrate (1) followed by Warm (1) Second mark conditional on first IGNORE ethanol as a solvent with water present Observation: white ppt (1) Max 3 A positive statement about the remaining liquid Logical plan L 10. (a) (i) Weighted average (mass) of 1 atom (1) on a scale in which 1 atom of 12C = 12 units / compared to 1/12 atom of 12C (1) 2 (ii) Number of protons plus / and neutrons nucleons in a nucleus / an atom. 1 (iii) Atoms of same atomic number / same proton number (1) which differ in the number of neutrons (1) (in the nucleus) 2 (b) (i) Concept of high energy electron collision: Electron bombardment / gun / acceleration / fired (1) knocks off electron / equation showing electron being knocked off (1) 2 (ii) Positive, +, S+ 1 (iii) Voltage differential across plates / charged plates [plural] / electrostatic field / electric field 1 (c) [ ] / 100 (1) = = (1) NOT (d) 1s²2s²2p63s²3p4 1 [9] [12] NT Exampro 6

Number of neutrons. what name is given to these different atoms of gallium? Isotopes (1)

Number of neutrons. what name is given to these different atoms of gallium? Isotopes (1) 1. (a) Complete the following table Atom Number of protons Number of neutrons Number of electrons 191 77 96 42 Ir Mo pne Ir7711477 Mo425442 (b) The element gallium consists of two types of atom of relative