Zadania wzorowane na pytaniach z tego arkusza: te same umiejętności, format i punktacja, inne dane i kontekst. Treści arkusza IB nie publikujemy.
Dodaj cały arkusz do zestawu(i) Determine the limiting reactant when 2.00 g of this powder reacts. (ii) Determine the volume, in dm3, of carbon dioxide released in the reaction in (i) at SATP. Use sections 1, 2 and 4 of the data booklet. (iii) A student collects 0.190…
The structure of a tartaric acid molecule is shown. (i) State how many hydrogen atoms in a tartaric acid molecule are acidic. (ii) Deduce the structural formula of the conjugate base of tartaric acid. (iii) Predict, giving a reason, whether tartaric acid is a…
A solution has a hydrogen ion concentration [H+] = 0.0063 mol dm−3. Calculate its pH.
Describe the bonding between the ions in solid disodium tartrate, Na2C4H4O6.
State, giving a reason, how the lattice enthalpy of lithium tartrate, Li2C4H4O6, would differ from that of sodium tartrate.
(i) Calculate, in J, the thermal energy gained by the water. Use sections 1 and 2 of the data booklet. (ii) Determine the percentage uncertainty of the energy value from (i). (iii) Suggest one way to reduce the effect of random uncertainty on the final result.
(i) Determine the molar enthalpy of combustion of butan-1-ol, in kJ mol−1, and state one assumption you made. If you did not obtain an answer to 2a(i), use 20 000 J, but this is not the correct value. (ii) Calculate the percentage error of your…
A second spirit burner contains hexane, C6H14, instead of butan-1-ol. Determine whether hexane would release more or less energy per gram than butan-1-ol. Use section 14 of the data booklet.
Methanol and butan-1-ol are members of the same homologous series. (i) Name the class of compound and the functional group that characterize this series. (ii) State the strongest intermolecular force between molecules of either alcohol. (iii) Predict one type…
Pentan-2-ol is optically active. (i) Sketch the two enantiomers of pentan-2-ol, showing how they are related. (ii) Deduce the organic product formed in each case when pentan-1-ol and pentan-2-ol are refluxed with acidified potassium dichromate(VI).…
Butan-1-ol can be produced from 1-bromobutane. (i) Identify a nucleophile that would convert 1-bromobutane into butan-1-ol. (ii) Using curly arrows, sketch the mechanism for the reaction of 1-bromobutane with the nucleophile you identified in (i).
An ester used as a pear flavouring is made by heating ethanoic acid with propan-1-ol in the presence of concentrated sulfuric acid: CH3COOH + CH3CH2CH2OH → CH3COOCH2CH2CH3 + X (i) Identify the type of reaction. (ii) Identify the second product, X, of…
Deduce the expression for Kc of this reaction.
Predict, with a reason, the effect of increasing the total pressure, at constant temperature, on the position of equilibrium.
Explain why a higher temperature speeds up this reaction, with the help of annotations that you add to the Maxwell-Boltzmann distribution below, which is drawn for a temperature T1.
The Maxwell-Boltzmann distribution for the uncatalysed reaction at temperature T1 is shown below. Add annotations to show how a catalyst changes the situation.
The reaction takes place on the surface of a nickel catalyst. The following mechanism is proposed, in which Ni-C represents carbon atoms bonded to the nickel surface: CH4 + Ni → Ni−C + 2 H2 (slow) Ni−C + CO2 → Ni−CO + CO (fast)…
Use section 13 of the data booklet and the standard molar entropy of hydrogen, S⊖(H2(g)) = +130.7 J K−1 mol−1, to calculate ΔS⊖ for the forward reaction, in J K−1.
At 1200 K, calculate ΔG⊖ for the forward reaction and the value of the equilibrium constant, K. Use sections 1 and 2 of the data booklet. If you were unable to obtain an answer for 3f, use 230 J K−1, but this is not the correct…
Determine the minimum temperature, in K, at which the forward reaction is spontaneous. Use section 1 of the data booklet. If you were unable to obtain an answer for 3f, use 230 J K−1, but this is not the correct value.
(i) State the oxidation states of carbon in carbon monoxide and in carbonyl chloride. (ii) For each of CO and Cl2 in the forward reaction, state whether it acts as an oxidizing agent or a reducing agent, and whether it is oxidized or reduced.
(i) Draw the Lewis (electron dot) structure of carbonyl chloride. (ii) Mark the bond polarities on your Lewis structure using the symbols δ+ and δ−. (iii) Explain the shape of the carbonyl chloride molecule and whether it is polar. (iv) State…
Identify the group to which element E belongs and justify your choice using the data.
Element E forms the oxoanion EO43−. Two possible Lewis structures of the ion are shown, with lone pairs drawn as dots. (i) Use formal charges to show which of the two structures is the better representation of the ion. (ii) The oxide E4O10…
In a titration, 25.0 cm3 of 0.100 mol dm−3 ethanoic acid, CH3COOH, was placed in a flask and 0.100 mol dm−3 sodium hydroxide solution was added from a burette. The pH curve is shown. (i) Using section 18 of the…
Use the mass spectrum shown to determine the relative atomic mass of chromium.
(i) Deduce the nuclear symbol, ZAX, of the chromium-52 ion that contains 21 electrons. (ii) Complete the orbital diagram of this ion by drawing an arrow for each electron. (iii) Predict whether this ion is paramagnetic or diamagnetic and…
The complex ion [Cr(H2O)6]3+ is violet and absorbs light most strongly at about 580 nm. The complex ion [Cr(NH3)6]3+ is orange and absorbs light most strongly at about 465 nm. (i) Explain why the two complex ions have different colours. Use…
Complete the diagram of a standard hydrogen electrode by writing in each box the feature that it points to.
A standard hydrogen electrode is connected to a half-cell consisting of a zinc rod in a solution of zinc nitrate, Zn(NO3)2(aq), to form a voltaic cell. (i) Write the cell diagram for the spontaneous reaction, using "|" for a phase boundary and "||" for…