Zadanie 1a
Outline why the first ionization energies of all the elements in the table are positive, whereas the first electron affinities of most of them are negative.
Chemistry SL Paper 3, May 2023, TZ1
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 zestawuZadanie 1c
The first electron affinity of magnesium is positive. Sketch the 3s and 3p orbital filling diagram of the species formed when one electron is added to a gaseous magnesium atom.
- Materiał graficzny
Zadanie 1d
Suggest one reason why the first electron affinity of magnesium is positive.
Zadanie 1e
Suggest reasons why argon has the largest first ionization energy and the largest positive first electron affinity of the elements in period 3. Largest first ionization energy: Largest positive first electron affinity:
Zadanie 1f
Suggest whether the first electron affinity of xenon is greater or smaller than that of argon, and give one reason for your answer.
Zadanie 2a
(i) Identify the oxidation state of metal S in SSO4. (ii) Deduce the order of reactivity of the five metals, from the most reactive to the least reactive.
Zadanie 2b
Sketch the voltaic cell that would produce the greatest cell potential (EMF) using the metals and solutions in this experiment. On your diagram label the metal and the solution in each half-cell, the anode, the cathode, the salt bridge and the direction of…
Zadanie 2c
Deduce the products formed at each electrode during the electrolysis of molten magnesium iodide, MgI2. Anode (positive electrode): Cathode (negative electrode):
Zadanie 3a
Iron is extracted in a blast furnace by reducing iron(III) oxide with carbon monoxide. Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g) Calculate the percentage atom economy for the production of iron by this reaction. Use section 1 of the data booklet.
Zadanie 4a
Brass is an alloy of copper and zinc. Explain why brass is harder and stronger, but a poorer conductor of electricity, than pure copper.
Zadanie 4b
The concentration of copper(II) ions in a sample of pond water is determined with a colorimeter. The absorbance of standard solutions of known concentration is measured and a calibration curve is plotted. Sketch the typical shape of the calibration curve on…
- Materiał graficzny
Zadanie 5b
The structures of three natural compounds X, Y and Z are shown. (i) Identify one functional group present in all three compounds. (ii) Identify one functional group present only in compound Z.
- Materiał graficzny
Zadanie 6a
Glucose, C6H12O6, is oxidized in the body by respiration to carbon dioxide and water. The standard enthalpy of combustion of glucose is −2803 kJ mol−1. Determine the energy, in kJ, released by the complete oxidation of 12.5 g of glucose.
Zadanie 6b
Sucrose, C12H22O11, and the triglyceride glyceryl tripalmitate, C51H98O6, can both be completely oxidized in the body to carbon dioxide and water. Write balanced equations for the complete oxidation of each compound. C12H22O11:…
Zadanie 7a
Determine the identity of the amino acid in spot B by calculating its RF value from the chromatogram.
- Materiał graficzny
Zadanie 7b
Spot X is known to be either glutamine or isoleucine. The structures of the two amino acids are shown. Predict, with reference to the structures, which amino acid is more likely to be in spot X. Use the RF values in the table.
- Materiał graficzny
Zadanie 11a
Methanol, CH3OH, can be used as a fuel. The standard enthalpy of combustion of methanol is −726 kJ mol−1. Calculate the mass of carbon dioxide produced per 1000 kJ of heat released by the complete combustion of methanol.
Zadanie 11b
The global warming potential (GWP) of a gas compares the heat it absorbs with the heat absorbed by an equal mass of carbon dioxide. The GWP of the refrigerant C2H2F4 is approximately 1300. Estimate the heat absorbed by one mole of C2H2F4 relative…
Zadanie 13a
Calcium carbonate and magnesium hydroxide are two antacids. Write an equation for the reaction of each antacid with excess hydrochloric acid in the stomach. Calcium carbonate: Magnesium hydroxide:
Zadanie 13b
One antacid tablet contains 1.50 g of calcium carbonate and a second tablet contains 1.50 g of magnesium hydroxide. Show by calculation that the tablet of magnesium hydroxide would neutralize more hydrochloric acid than the tablet of calcium carbonate.