AQA A Level Chemistry Paper 1 Questions And
Answers
/. What is the general equation for the reaction of [M(H2O)6]3+ with NH3? (1)
Give the observations seen of the iron and aluminium complexes (2)
1. [M(H2O)6]3+ + 3NH3 -> [M(H2O)3(OH)3] + 3NH4+
2. Fe(III) - orange/brown ppt
3. Al(III) - white ppt
/.Define the term enthalpy of lattice formation (2)
1. enthalpy change when one mole of ionic lattice
2. is formed from its gaseous ions
/.Identify a reagent that could be used to indicate the presence of iodide ions in
an aqueous solution and describe the observation made (2)
1. AgNO3
2. yellow ppt
/.Suggest why pure water at 10 degrees (pH>7) is not alkaline (1)
1. [H+]=[OH-]
/.State the term of the meaning transition metal complex (1)
1. a central metal ion surrounded by ligands
/.Draw the shape of a PF3 molecule, include lone pairs (1)
Name the shape (1)
,trigonal pyramidal
Suggest why the oxidation state of chromium is zero in Cr(PF3)6 (1)
1. PF3 has no overall charge and the complex has no overall charge
/.Deduce the oxidation state of chromium in the [Cr(NH3)4Cl2] (1)
1. +2
/.Name the type of bond between N and H in ammonia (1)
1. covalent bond
Draw the two isomers of [Cr(NH3)4Cl2]+ (2)
/.State the isomerism shown (1)
cis/trans isomerism
/.Complete the equation to show the formation of one complex that contains
chromium in its +3 oxidation state (1)
CrCl3 + 5H2O ->
1. [Cr(H2O)5Cl]Cl2
/.Give the electron configuration of the Al3+ ion (1)
1. 1s2, 2s2, 2p6
/.Give the equation for the reaction between Al2(SO4)3 and water forming a
solution containing the complex ion [Al(H2O)6]3+ (1)
1. Al2(SO4)3 + 12H2O -> 2[Al(H2O)6]3+ + 3SO42-
/.Explain why the solution containing [Al(H2O)6]3+ is acidic (2)
1. Al3+ has a high charge and small size/high charge density
2.AL3+ weakens the O-H bond in water ligand and donates H+ to water
, /.State why the concentration of aluminium sulfate solution can't be determined
by colorimetry (1)
1. its a colourless solution
/.Give the ionic equation for the reaction of [Al(H2O)6]3+ with excess aqueous
ammonia (1)
State one observation (1)
1. [Al(H2O)6]3+ + 3NH3 -> [Al(H2O)3(OH)3] + 3NH4+
2. white ppt
/.State the meaning of the term electrochemical series (1)
1. electrode potentials in numerical order
/.State the equations which go on at the positive electrode (cathode) and negative
electrode (anode) for a lithium ion cell (2)
Deduce the overall equation of the reaction (1)
State the cell EMF (1)
1. cathode: Li+ + CoO2 + e- -> LiCoO2
2. anode: Li+ + e- -> Li
3. overall equation: CoO2 + Li → LiCoO2 (for charging, the equation is the other
way around)
4. cell EMF: +0.6 - -3.00 = 3.6 V
/.State the equations which go on at the positive electrode (cathode) and negative
electrode (anode) for a hydrogen-oxygen fuel cell (2)
Deduce the overall equation of the reaction (1)
State the cell EMF (1)
1. cathode: O2 + 2 H2O + 4 e- -> 4 OH-
2. anode: H2 + 2OH- -> 2H2O + 2e-
3. overall equation: 2H2 + O2. -> 2H2O
4. cell EMF: +0.4 - -0.83 = 1.23 V
/.State the property of SO2 that causes pollution when it enters rivers (1)
Give an equation for the reaction of SO2 with water (1)
1. acidic
Answers
/. What is the general equation for the reaction of [M(H2O)6]3+ with NH3? (1)
Give the observations seen of the iron and aluminium complexes (2)
1. [M(H2O)6]3+ + 3NH3 -> [M(H2O)3(OH)3] + 3NH4+
2. Fe(III) - orange/brown ppt
3. Al(III) - white ppt
/.Define the term enthalpy of lattice formation (2)
1. enthalpy change when one mole of ionic lattice
2. is formed from its gaseous ions
/.Identify a reagent that could be used to indicate the presence of iodide ions in
an aqueous solution and describe the observation made (2)
1. AgNO3
2. yellow ppt
/.Suggest why pure water at 10 degrees (pH>7) is not alkaline (1)
1. [H+]=[OH-]
/.State the term of the meaning transition metal complex (1)
1. a central metal ion surrounded by ligands
/.Draw the shape of a PF3 molecule, include lone pairs (1)
Name the shape (1)
,trigonal pyramidal
Suggest why the oxidation state of chromium is zero in Cr(PF3)6 (1)
1. PF3 has no overall charge and the complex has no overall charge
/.Deduce the oxidation state of chromium in the [Cr(NH3)4Cl2] (1)
1. +2
/.Name the type of bond between N and H in ammonia (1)
1. covalent bond
Draw the two isomers of [Cr(NH3)4Cl2]+ (2)
/.State the isomerism shown (1)
cis/trans isomerism
/.Complete the equation to show the formation of one complex that contains
chromium in its +3 oxidation state (1)
CrCl3 + 5H2O ->
1. [Cr(H2O)5Cl]Cl2
/.Give the electron configuration of the Al3+ ion (1)
1. 1s2, 2s2, 2p6
/.Give the equation for the reaction between Al2(SO4)3 and water forming a
solution containing the complex ion [Al(H2O)6]3+ (1)
1. Al2(SO4)3 + 12H2O -> 2[Al(H2O)6]3+ + 3SO42-
/.Explain why the solution containing [Al(H2O)6]3+ is acidic (2)
1. Al3+ has a high charge and small size/high charge density
2.AL3+ weakens the O-H bond in water ligand and donates H+ to water
, /.State why the concentration of aluminium sulfate solution can't be determined
by colorimetry (1)
1. its a colourless solution
/.Give the ionic equation for the reaction of [Al(H2O)6]3+ with excess aqueous
ammonia (1)
State one observation (1)
1. [Al(H2O)6]3+ + 3NH3 -> [Al(H2O)3(OH)3] + 3NH4+
2. white ppt
/.State the meaning of the term electrochemical series (1)
1. electrode potentials in numerical order
/.State the equations which go on at the positive electrode (cathode) and negative
electrode (anode) for a lithium ion cell (2)
Deduce the overall equation of the reaction (1)
State the cell EMF (1)
1. cathode: Li+ + CoO2 + e- -> LiCoO2
2. anode: Li+ + e- -> Li
3. overall equation: CoO2 + Li → LiCoO2 (for charging, the equation is the other
way around)
4. cell EMF: +0.6 - -3.00 = 3.6 V
/.State the equations which go on at the positive electrode (cathode) and negative
electrode (anode) for a hydrogen-oxygen fuel cell (2)
Deduce the overall equation of the reaction (1)
State the cell EMF (1)
1. cathode: O2 + 2 H2O + 4 e- -> 4 OH-
2. anode: H2 + 2OH- -> 2H2O + 2e-
3. overall equation: 2H2 + O2. -> 2H2O
4. cell EMF: +0.4 - -0.83 = 1.23 V
/.State the property of SO2 that causes pollution when it enters rivers (1)
Give an equation for the reaction of SO2 with water (1)
1. acidic
