T3-2P3 [51 marks] Bromine is a member of group 7, the halogens. [3 marks] Explain the trend in reactivity of the halogens. 1a.

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1 T3-2P3 [51 marks] Bromine is a member of group 7, the halogens. 1a. Explain the trend in reactivity of the halogens. [3 marks] 1b. Deduce, using equations where appropriate, if bromine reacts with sodium chloride solution and with sodium iodide solution. Iron is a transition metal. 1c. Describe the bonding in metals and explain their malleability. [3 marks]

2 1d. List three characteristic properties of transition elements. 1e. Identify the type of bonding between iron and cyanide in [Fe(CN) 6 ] 3. 1f. Deduce the oxidation number of iron in [Fe(CN) 6 ] 3. 1g. Draw the abbreviated orbital diagram for an iron atom using the arrow-in-box notation to represent electrons. 3

3 1h. Draw the abbreviated orbital diagram for the iron ion in [Fe(CN) 6] 3 using the arrow-in-box notation to represent electrons. Freshly prepared iron(ii) bromide can be electrolysed both in the liquid state and in aqueous solution. 1i. Describe, using a diagram, the essential components of an electrolytic cell. [3 marks] 1j. Describe the two ways in which current is conducted in an electrolytic cell.

4 Predict and explain the products of electrolysis of a dilute iron(ii) bromide solution. 1k. [4 marks] 1l. Identify another product that is formed if the solution of iron(ii) bromide is concentrated. 1m. Explain why this other product is formed.

5 Chlorine occurs in Group 7, the halogens. Two stable isotopes of chlorine are 35 Cl and 37 Cl with mass numbers 35 and 37 respectively. Define the term isotopes of an element. 2a. 2b. Calculate the number of protons, neutrons and electrons in the isotopes 35Cl and 37Cl. 2c. Using the mass numbers of the two isotopes and the relative atomic mass of chlorine from Table 5 of the Data Booklet, determine the percentage abundance of each isotope. Percentage abundance 35Cl: Percentage abundance 37Cl:

6 Chlorine has an electronegativity value of 3.2 on the Pauling scale. 2d. Define the term electronegativity. 2e. Using Table 7 of the Data Booklet, explain the trends in electronegativity values of the Group 7 elements from F to I. 2f. State the balanced chemical equation for the reaction of potassium bromide, KBr(aq), with chlorine, Cl (aq). 2 2g. Describe the colour change likely to be observed in this reaction.

7 Chloroethene, H2C=CHCl, the monomer used in the polymerization reaction in the manufacture of the polymer poly(chloroethene), PVC, can be synthesized in the following two-stage reaction pathway. Stage 1: Stage 2: C 2 H 4 (g) + Cl 2 (g) ClCH 2 CH 2 Cl(g) ClCH 2 CH 2 Cl(g) + HC=CHCl(g) + HCl(g) Determine the enthalpy change, ΔH, in kj mol 1, for stage 1 using average bond enthalpy data from Table 10 of the Data 2h. Booklet. [3 marks] 2i. State whether the reaction given in stage 1 is exothermic or endothermic. 2j. Draw the structure of poly(chloroethene) showing two repeating units.

8 2k. Suggest why monomers are often gases or volatile liquids whereas polymers are solids. 3. Which statements are correct for the oxides of period 3 going from Na to Cl? I. The oxides become increasingly acidic. II. III. The bonding of the oxides changes from ionic to covalent. All the oxides dissolve readily in water. A. I and II only B. I and III only C. II and III only D. I, II and III 4. The elements argon, potassium, and calcium are consecutive in the periodic table. Which gives the correct order of increasing first ionization energies? A. B. C. D. Ar < Ca < K K < Ar < Ca Ca < K < Ar K < Ca < Ar 5. Which properties decrease down both group 1 and group 7? I. Melting point II. First ionization energy III. Electronegativity A. I and II only B. I and III only C. II and III only D. I, II and III 6. Which period 3 oxide, when added to water, forms an acidic solution? A. SO 3 B. MgO C. D. Na 2 O Al 2 O 3 7. Which statements about reactivity are correct? I. Potassium reacts more vigorously than sodium with chlorine. II. III. Lithium reacts more vigorously than potassium with water. Fluorine reacts more vigorously than bromine with a potassium iodide solution. A. I and II only B. I and III only C. II and III only D. I, II and III

9 8. The horizontal axis of the bar chart represents the elements of period 3 from sodium to chlorine (excluding silicon). What could the vertical axis represent? A. Melting point of the element B. Electronegativity of the bonded atom C. Ionic radius of the most common ion D. First ionization energy in the gaseous state 9. The electronegativities of four elements are given in the table. Which statement is correct? A. W and X form an ionic compound. B. W and X form a covalent compound. C. Y and Z form an ionic compound. D. Y and Z form a covalent compound. 10. Which properties decrease down group 1? I. Melting point II. III. Atomic radius First ionization energy A. I and II only B. I and III only C. II and III only D. I, II and III International Baccalaureate Organization 2017 International Baccalaureate - Baccalauréat International - Bachillerato Internacional Printed for BLUPS