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Acidic and Basic Character of Organic Compounds · CAPE Chemistry Unit 2

92 past-paper questions on Acidic and Basic Character of Organic Compounds, part of The Chemistry of Carbon Compounds, from every CAPE Chemistry Unit 2 paper on Quelpr.

Practise Acidic and Basic Character of Organic Compounds
  1. 1(a)(i)a2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Suggest how the blood responds in the presence of lactic acid produced as a result of mild exercise.
  2. 1(a)(i)b2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Suggest how the blood responds in the presence of lactic acid produced as a result of strenuous exercise.
  3. 1(a)(ii)2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Suggest how the blood responds in the presence of excess alkalinity.
  4. 2(a)6 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Outline a plan by which a chemist, without access to flame test rods, could use physical properties to identify the four Group II metal sulphates (Mg, Ca, Sr, Ba).
  5. 2(b)(i)1 mark· CAPE Chemistry Unit 2 · 2005 · Paper 2Describe the environmental conditions under which a photographer would have decided to use the reaction of heating magnesium in air.
  6. 2(b)(ii)1 mark· CAPE Chemistry Unit 2 · 2005 · Paper 2Suggest ONE disadvantage of using the reaction of magnesium burning in air for photography.
  7. 2(b)(iii)2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Write the chemical equation to illustrate the reaction of magnesium burning in air.
  8. 4(a)5 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2By reference to the Bronsted-Lowry theory and the molecular structure of niacin, explain the statement, "Niacin is a weak acid".
  9. 4(c)(i)3 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2What changes in the values of pH and Ka for niacin would be expected if the determination is carried out at 320 K? Suggest a reason based on molecular structure.
  10. 5(a)(i)1 mark· CAPE Chemistry Unit 2 · 2005 · Paper 2Explain the "muscle twitch" observed by Galvani when frog leg muscles were touched simultaneously by two different metals.
  11. 5(a)(ii)3 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Describe with the aid of a diagram the experiment that Volta might have performed using TWO named metals to produce electricity.
  12. 5(a)(iii)5 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Describe how the apparatus in (a)(ii) can be modified to determine the standard electrode potential.
  13. 5(c)(i)2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Use the data booklet to write equations for the reactions occurring at each electrode during discharge of the lead-storage battery.
  14. 5(c)(ii)2 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Calculate the standard cell potential for the lead-storage battery.
  15. 5(d)3 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2By reference to standard electrode potentials in the data booklet, deduce the useful by-product of the H2-O2 fuel cell reaction, including relevant equations.
  16. 7(a)(i)4 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Explain why anhydrous copper (II) sulphate is a white solid that gradually turns blue upon dropwise addition of water, and dissolves to form a blue solution upon further addition.
  17. 7(a)(ii)3 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Explain why the gradual addition of concentrated sodium chloride solution to aqueous copper (II) sulphate produces a green solution, which changes to yellow upon further addition.
  18. 7(b)(i)4 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Determine the formula of the complex ion X.
  19. 7(b)(ii)1 mark· CAPE Chemistry Unit 2 · 2005 · Paper 2Draw the shape of the complex ion X.
  20. 7(c)(i)4 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Explain why the oxygen-carrying capacity of haemoglobin is reduced in the presence of carbon monoxide.
  21. 7(c)(ii)4 marks· CAPE Chemistry Unit 2 · 2005 · Paper 2Account for why manganate(VII) ions (MnO4-) and dichromate(VI) ions (Cr2O7 2-) are powerful oxidizing agents, using E0 values where appropriate.
  22. 1(a)(i)2 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Predict quantitatively the effect on the rate of reaction when the concentration of H₂(g) is doubled, and give a reason.
  23. 1(a)(ii)2 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Predict quantitatively the effect on the rate of reaction when the concentration of NO(g) is halved, and give a reason.
  24. 1(a)(iii)1 mark· CAPE Chemistry Unit 2 · 2006 · Paper 2Predict quantitatively the effect on the rate of reaction when the concentrations of H₂(g) and NO(g) are both tripled.
  25. 1(b)(i)2 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Sketch a suitable graph representing the data collected (volume of products formed versus time).
  26. 1(b)(ii)1 mark· CAPE Chemistry Unit 2 · 2006 · Paper 2Apart from volume measurement, state ONE other method of monitoring the rate of this reaction.
  27. 1(b)(iii)2 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Suggest TWO precautions that should be taken when performing the experiment in (b)(ii).
  28. 5(c)(i)3 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Explain how the molecular structure of amino acids relates to their function as buffers in human blood.
  29. 6(a)(i)6 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Explain the trend in the bonding and acid/base character of the Group IV oxides in the +2 state.
  30. 6(a)(ii)2 marks· CAPE Chemistry Unit 2 · 2006 · Paper 2Explain the trend in the behaviour of the Group IV tetrachlorides on reacting with water.
  31. 1(a)(ii)2 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Write the expression for the equilibrium constant, K_c.
  32. 1(b)(i)3 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2In an experiment to monitor the equilibrium, the mixture contains 0.0389 mol of Br2, 0.0111 mol of Cl2, and 0.0546 mol of BrCl. Given that K_c at 298 K is 6.88, determine whether equilibrium has been attained in the…
  33. 1(b)(iii)1 mark· CAPE Chemistry Unit 2 · 2007 · Paper 2Suggest ONE safety measure that should be taken in this experiment.
  34. 1(c)1 mark· CAPE Chemistry Unit 2 · 2007 · Paper 2Under what experimental condition would the value of K_c be greater than 6.90, given that the reaction is endothermic?
  35. 6(b)(i)1 mark· CAPE Chemistry Unit 2 · 2007 · Paper 2State the acid/base character of MgO.
  36. 6(c)(i)2 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Write a balanced equation for the reaction of Na2O with water.
  37. 6(d)2 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Give the approximate pH of the solution formed from the reactions in (c)(i) and (c)(ii).
  38. 6(e)4 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Explain why SiCl4 is a liquid at room temperature and pressure whereas SiO2 is a solid with a high melting point, in terms of structure and bonding.
  39. 7(c)4 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Classify the acid/base character of the Group IV dioxides and explain how it relates to the type of bonding.
  40. 7(d)2 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Use the provided standard electrode potentials to comment on the relative stability of the +4 and +2 oxidation states of Ge, Sn, and Pb.
  41. 7(e)4 marks· CAPE Chemistry Unit 2 · 2007 · Paper 2Explain why Sn2+ ions will reduce orange Cr2O7^2- to green Cr3+ but Pb2+ ions will not, referencing standard electrode potentials and using suitable half-equations.
  42. 4(a)6 marks· CAPE Chemistry Unit 2 · 2008 (T&T) · Paper 2Complete Table 1 by predicting the outcome (products or no reaction) for the reactions of ethanol, phenol, and ethanoic acid with Na2CO3, Na, and NaOH.
  43. 4(b)4 marks· CAPE Chemistry Unit 2 · 2008 (T&T) · Paper 2With reference to the Lewis structure and resonance forms of the phenoxide ion and the Lewis structure of the alkoxide ion, compare and explain the difference in acidity between alcohols and phenols.
  44. 1(b)(i)2 marks· CAPE Chemistry Unit 2 · 2009 · Paper 2Write a general equation showing the basic property of phenylamine.
  45. 1(b)(ii)a)1 mark· CAPE Chemistry Unit 2 · 2009 · Paper 2State whether phenylamine is more basic or less basic than ammonia.
  46. 1(b)(ii)b)4 marks· CAPE Chemistry Unit 2 · 2009 · Paper 2Explain your answer in terms of availability of lone pairs and hydrogen bonding.
  47. 4(a)(iv)4 marks· CAPE Chemistry Unit 2 · 2009 · Paper 2Write the displayed formula of the species present in aqueous solutions of alanine at: a) pH = 2, b) pH = 13, c) pH = 7.
  48. 1(d)1 mark· CAPE Chemistry Unit 2 · 2010 · Paper 2Write the general chemical structure of an amino acid.
  49. 4(c)5 marks· CAPE Chemistry Unit 2 · 2011 · Paper 2Explain the difference in acidity of alcohols, phenols and carboxylic acids, making reference to acid strength, inductive and conjugative effects.
  50. Q111 mark · multiple choice· CAPE Chemistry Unit 2 · 2012 · Paper 1Which of the following would release a proton MOST readily?
  51. Q131 mark · multiple choice· CAPE Chemistry Unit 2 · 2012 · Paper 1The pH of tyrosine is MOST likely
  52. Q441 mark · multiple choice· CAPE Chemistry Unit 2 · 2012 · Paper 1W would MOST likely be
  53. Q121 mark · multiple choice· CAPE Chemistry Unit 2 · 2013 · Paper 1The complete reaction of phenol with aqueous bromine is characterised by a
  54. Q131 mark · multiple choice· CAPE Chemistry Unit 2 · 2013 · Paper 1Which of the options below, (A), (B), (C) and (D), is correct for the properties shown by the following structures?
  55. 4(a)(i)1 mark· CAPE Chemistry Unit 2 · 2013 · Paper 2State the reagent needed to convert phenol into sodium phenoxide (reaction (i)).
  56. Q91 mark · multiple choice· CAPE Chemistry Unit 2 · 2014 · Paper 1Item 9 refers to the compounds, P, Q, R and S, whose structures are given below. P: \text{CH}_3(\text{CH}_2)_4\text{CH}_2\text{OH} Q: \text{CH}_3(\text{CH}_2)_3\text{CH}_2\text{COOH} R:…
  57. Q111 mark · multiple choice· CAPE Chemistry Unit 2 · 2014 · Paper 1The complete reaction of phenol with aqueous bromine is characterized by a
  58. Q121 mark · multiple choice· CAPE Chemistry Unit 2 · 2014 · Paper 1Which of the following organic compounds would release a proton MOST readily?
  59. Q131 mark · multiple choice· CAPE Chemistry Unit 2 · 2014 · Paper 1Item 13 refers to each of the three sets of structures shown below which are to be labelled as showing the conjugative effect or the positive inductive effect or the negative inductive effect. Which of the following…
  60. 1(b)(i)2 marks· CAPE Chemistry Unit 2 · 2014 · Paper 2Write the expression for the basic dissociation constant, Kb.
  61. 1(b)(ii)1 mark· CAPE Chemistry Unit 2 · 2014 · Paper 2The pKb values for ethylamine and phenylamine are 3.27 and 9.38 respectively. State which of these compounds is the stronger base.
  62. 1(b)(iii)2 marks· CAPE Chemistry Unit 2 · 2014 · Paper 2State TWO reasons for the difference between the two pKb values in (b)(ii).
  63. 1(c)(i)1 mark· CAPE Chemistry Unit 2 · 2014 · Paper 2Suggest a value for Kb for ethanamide, CH3CONH2.
  64. 1(c)(ii)1 mark· CAPE Chemistry Unit 2 · 2014 · Paper 2State a reason for your answer in (c)(i).
  65. Q151 mark · multiple choice· CAPE Chemistry Unit 2 · 2015 · Paper 1What would be OBSERVED when aqueous bromine is added to the following compound (phenol)?
  66. Q81 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1Which of the following equations is correct for the reaction of 4-methyl phenol with ethanoyl chloride?
  67. Q91 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1The correct sequence of the compounds, in order of DECREASING acid strength, is P: \text{CH}_3(\text{CH}_2)_4\text{CH}_2\text{OH} Q: \text{CH}_3(\text{CH}_2)_3\text{CH}_2\text{COOH} R:…
  68. Q111 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1Which of the following sets of pH values is LIKELY to be for the amines, X, Y and Z respectively? X: \text{CH}_2\text{Cl CH}_2\text{Cl NH}_2 Y: \text{CH}_3\text{ CH}_2\text{ NH}_2 Z:…
  69. Q131 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1Phenol and benzoic acid can be distinguished by their reaction with
  70. Q401 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1W would MOST likely be
  71. Q451 mark · multiple choice· CAPE Chemistry Unit 2 · 2016 · Paper 1Which of the following substances is a MAJOR component of biomass?
  72. 4(e)3 marks· CAPE Chemistry Unit 2 · 2016 · Paper 2Write the structural formula for the products formed when phenol is treated with (i) aqueous bromine, (ii) sodium hydroxide, (iii) ethanoyl chloride.
  73. 4(f)1 mark· CAPE Chemistry Unit 2 · 2016 · Paper 2Write the equation for the reaction in (e)(iii).
  74. Q151 mark · multiple choice· CAPE Chemistry Unit 2 · 2017 · Paper 1What would be OBSERVED when aqueous bromine is added to the following compound?
  75. 1(d)2 marks· CAPE Chemistry Unit 2 · 2017 · Paper 2Comment on the relative pKa values of Compound A and its chlorosubstituted compound in (c)(ii).
  76. 1(b)(i)2 marks· Chemistry · Unit 2 Q1 1(b)(i)Write an expression for the Kₐ of chloroethanoic acid.
  77. 1(b)(ii)1 mark· Chemistry · Unit 2 Q1 1(b)(ii)Write an expression to show how pKₐ is derived from Kₐ.
  78. 1(c)2 marks· Chemistry · Unit 2 Q1 1(c)Distinguish between a 'strong acid' and a 'weak acid'.
  79. 1(c)(i)4 marks· Chemistry · Unit 2 Q1 1(c)(i)Complete Table 1 above by correctly inserting the pKₐ value of EACH compound from the following list of values: 1.48, 0.70, 4.76 and 2.86.
  80. 1(c)(i)1 mark· Chemistry · Unit 2 Q1 1(c)(i)State the name of the reagent C.
  81. 1(c)(ii)5 marks· Chemistry · Unit 2 Q1 1(c)(ii)Give reasons for your assignments in (c)(i).
  82. 1(c)(v)3 marks· Chemistry · Unit 2 Q1 1(c)(v)Given that ethanol has a pKa of 16, suggest whether the pKa of Compound C is higher or lower than that of ethanol. Give a reason for your suggestion.
  83. 1(c)(v)2 marks· Chemistry · Unit 2 Q1 1(c)(v)State the colour changes which would be observed if litmus is added to a solution of primary amine, B.
  84. 1(c)(vii)2 marks· Chemistry · Unit 2 Q1 1(c)(vii)In an experiment, two drops of universal indicator were added to 1 cm³ of ethanol in Test tube 1 and 1 cm³ of Compound C in Test tube 2. Suggest the colours expected in Test tubes 1 and 2.
  85. 1(d)4 marks· Chemistry · Unit 2 Q1 1(d)Account for the fact that the pKₐ of phenylamine is greater than that of ethylamine.
  86. 1(d)3 marks· Chemistry · Unit 2 Q1 1(d)Using pKa values of 16, 4.8 and 0.6, complete Table 1 with the correct pKa value for EACH organic compound.
  87. 1(d)(i)3 marks· Chemistry · Unit 2 Q1 1(d)(i)Use the compound ethylamine CH3CH2NH2 and a relevant equation to explain the statement above.
  88. 1(d)(ii)4 marks· Chemistry · Unit 2 Q1 1(d)(ii)The pKb values for ethanamide, ethylamine and phenylamine are 14.51, 3.27 and 9.38 respectively. Account for the difference in these pKb values.
  89. 1(e)5 marks· Chemistry · Unit 2 Q1 1(e)Complete the table by inserting the appropriate observations and reagents.
  90. 4(c)(i)3 marks· Chemistry · Unit 2 Q4 4(c)(i)Explain the chemical process that can account for these observations.
  91. 4(c)(ii)1 mark· Chemistry · Unit 2 Q4 4(c)(ii)State ONE other example that demonstrates this process.
  92. 6(c)(ii)3 marks· Chemistry · Unit 2 Q6 6(c)(ii)Phosphorus and silicon are two other useful non-metals. List TWO uses of silicon and ONE use of phosphorus.

Related topics in The Chemistry of Carbon Compounds