Chapter 15 The p-block elements (I) Part1 The group 17elements(F,CI Br,I) 1.Which of the following correctly describes the trends in values of Pauling electronegativities(xP)and ionic radii(rion)? A.xP:F<CI<Br <I;rion:F<Cl<Br<I B.xP:F>Cl>Br>I;rion:F<Cl<Br<I C.xP:F<CI<Br<I;rion:F>Cl>Br>I D.xP:F>Cl>Br>I;rion:F>Cl>Br>I 2.The Br-Br distance in crystalline Br2 is 227 pm,but in the solid state structure of PhaPBr2 it is 312 pm.This is because: A.an ionic salt has formed B.electrons from a filled MO in Br2 have been donated to PPhs C.lone pair electrons from PPh3 have been donated to the Br2MO D.PhaPBr2 is trigonal bipyramidal and the two Br atoms are not bonded 3.Which statement is incorrect about the hydrogen halides? A.Each gaseous HX molecule is polar B.All are gases at 298K C.Bond dissociation energies for HX decrease down the group D.For each HX,the pK value is negative indicating that each is a strong acid 4.Match the shape to the formula.Which pairing is correct? A.[BrF2]';non-linear B.[ICl4]tetrahedral C.IFs;trigonal bipyramidal D.BrF,trigonal pyramidal
Chapter 15 The p-block elements ( ) Ⅲ Part1 The group 17 elements (F, Cl Br, I) 1. Which of the following correctly describes the trends in values of Pauling electronegativities (χP) and ionic radii (rion)? A. χP: F < Cl < Br < I; rion: F < Cl < Br < I B. χP: F > Cl > Br > I; rion: F < Cl < Br < I C. χP: F < Cl < Br < I; rion: F > Cl > Br > I D. χP: F > Cl > Br > I; rion: F > Cl > Br > I 2. The Br–Br distance in crystalline Br2 is 227 pm, but in the solid state structure of Ph3PBr2 it is 312 pm. This is because: A. an ionic salt has formed B. electrons from a filled MO in Br2 have been donated to PPh3 C. lone pair electrons from PPh3 have been donated to the Br2 σ* MO D. Ph3PBr2 is trigonal bipyramidal and the two Br atoms are not bonded 3. Which statement is incorrect about the hydrogen halides? A. Each gaseous HX molecule is polar B. All are gases at 298 K C. Bond dissociation energies for HX decrease down the group D. For each HX, the pKa value is negative indicating that each is a strong acid 4. Match the shape to the formula. Which pairing is correct? A. [BrF2] + ; non-linear B. [ICl4] – ; tetrahedral C. IF5; trigonal bipyramidal D. BrF3; trigonal pyramidal 1
5.Which reaction is not likely to occur? A.CsF+F7→CsF] B.CsF+BrF3→Cs[BrF4l C.2SbFs+BrFs[BrF4][Sb2Fn] D.CIF3+BF3-[BF2][CIF4] 6.Which of the following oxides is paramagnetic? A.Cl2O B.C102 C.C1206 D.C10 7.Cl2O7 is the anhydride of: A.HOCI B.HClO2 C.HCIO; D.HCIO4 8.Which statement is incorrect about oxoacids of the halogens? A.HCIO is a liquid at 298 K B.HOCI and HOBr have not been isolated C.HCIO and HCIO behave as weak acids in aqueous solution D.Aqueous HIO is relatively strong acid with pK< 9.Which statement about perchlorates is incorrect? A.[CIOis difficult to reduce in dilute solution because it is kinetically stable B.[CIO is a strongly coordinating ion and is much used in complex formation C.Perchlorates are potentially explosive D.The [CIOion is tetrahedral
5. Which reaction is not likely to occur? A. CsF + IF7 → Cs[IF8] B. CsF + BrF3 → Cs[BrF4] C. 2SbF5 + BrF5 → [BrF4][Sb2F11] D. ClF3 + BF3 → [BF2][ClF4] 6. Which of the following oxides is paramagnetic? A. Cl2O B. ClO2 C. Cl2O6 D. Cl2O7 7. Cl2O7 is the anhydride of: A. HOCl B. HClO2 C. HClO3 D. HClO4 8. Which statement is incorrect about oxoacids of the halogens? A. HClO4 is a liquid at 298 K B. HOCl and HOBr have not been isolated C. HClO4 and HClO3 behave as weak acids in aqueous solution D. Aqueous HIO3 is relatively strong acid with pKa < 1 9. Which statement about perchlorates is incorrect? A. [ClO4] – is difficult to reduce in dilute solution because it is kinetically stable B. [ClO4] – is a strongly coordinating ion and is much used in complex formation C. Perchlorates are potentially explosive D. The [ClO4] – ion is tetrahedral 2
10.Titration of I2 against thiosulfate is a standard laboratory titration.Which statement is correct? A.Solutions of are prepared in aqueous KI because I is insoluble in water B.is oxidized during the titration C.[S2O3is reduced during the titration D.No indicator is usually used in this redox titration 11.Which interhalogen compound or cation is not,at present,known? A.CIF7 B.[BrFcJ' C.IF7 D.[CIFsT 12.In which reaction is iodine oxidized? A.2+B2→2IBr B.IFs+2SbFs-[IF4][Sb2Fu] C.205+H0→2HIO3 D.IF3+MeNF→Me4NIF 13.In which solid-state structure is F-octahedrally sited? A.KF B.CaF2 C.BeF2 D.HF 14.Hypochlorous acid and perchloric acid are,respectively A.HOCI and HCIO4 B.HOCI and HCIO C.HCIO2 and HCIO D.HCIO2 and HCIO
10. Titration of I2 against thiosulfate is a standard laboratory titration. Which statement is correct? A. Solutions of I2 are prepared in aqueous KI because I2 is insoluble in water B. I2 is oxidized during the titration C. [S2O3] 2– is reduced during the titration D. No indicator is usually used in this redox titration 11. Which interhalogen compound or cation is not, at present, known? A. ClF7 B. [BrF6] + C. IF7 D. [ClF6] + 12. In which reaction is iodine oxidized? A. I2 + Br2 → 2IBr B. IF5 + 2SbF5 → [IF4][Sb2F11] C. I2O5 + H2O → 2HIO3 D. IF3 + Me4NF → [Me4N][IF4] 13.In which solid-state structure is F– octahedrally sited? A. KF B. CaF2 C. BeF2 D. HF 14. Hypochlorous acid and perchloric acid are, respectively: A. HOCl and HClO4 B. HOCl and HClO3 C. HClO2 and HClO3 D. HClO2 and HClO4 3
15.Which of the following statements is incorrect? A.KBrO is a strong reducing agent and is used in volumetric analysis B.HIO,is a white solid at 298K C.Perchlorate salts are potentially explosive D.NaClO;is a commercial bleaching agent 16.Match the following molecules or ions to their shapes.Which pairing is correct? A.[I3]';bent B.BrFs;trigonal bipyramidal C.CIF3;trigonal planar D.[BrF square planar 17.Consider [IFs]With which arrangement of atoms is the VSEPR model consistent? A.Trigonal bipyramidal B.Pentagonal planar C.Square-based pyramidal D.Pentagonal bipyramidal 18.A potential diagram for bromine at pH 14 shows the following E values BrOJ→Br-E=+0.61V BrOj→Br-E°=+0.76V What is the value of Eo for the reduction of [BrO3T to [BrO]? A.+0.54V B.-0.15V C.+0.46V D.+1.37V 19.Which one of the following is a disproportionation reaction?
15. Which of the following statements is incorrect? A. KBrO3 is a strong reducing agent and is used in volumetric analysis B. HIO3 is a white solid at 298 K C. Perchlorate salts are potentially explosive D. NaClO3 is a commercial bleaching agent 16. Match the following molecules or ions to their shapes. Which pairing is correct? A. [I3] - ; bent B. BrF5 ; trigonal bipyramidal C. ClF3 ; trigonal planar D. [BrF4] - ; square planar 17. Consider [IF5] 2-. With which arrangement of atoms is the VSEPR model consistent? A. Trigonal bipyramidal B. Pentagonal planar C. Square-based pyramidal D. Pentagonal bipyramidal 18. A potential diagram for bromine at pH 14 shows the following Eo values: [BrO3] - → Br- Eo = +0.61 V [BrO]- → Br- Eo = +0.76 V What is the value of Eo for the reduction of [BrO3] - to [BrO]- ? A. +0.54 V B. -0.15 V C. +0.46 V D. +1.37 V 19. Which one of the following is a disproportionation reaction? 4
A.l2+r→ B.Cl2+2[OH→C+[OCI叮+H20 C.B+3[OCI叮→BrO+3Cr D.HOI+2HCI→H++C+HO 20.In which one of the following reactions is at least one iodine atom oxidized? A.IFs+2SbFs-[IFa][Sb2Fu] B.CsIC]→CsCI+ICI C.2+r→ D.2L2+S206F2→2][S0,F] ANSWERS: 1.Which of the following correctly describes the trends in values of Pauling electronegativities(xP)and ionic radii(rion)? Correct Answer:xP:F>CI>Br>I;rion:F<CI<Br<I 2.The Br-Br distance in crystalline Br2 is 227 pm,but in the solid state structure of Ph3PBr2 it is 312 pm.This is because: Correct Answer:lone pair electrons from PPhs have been donated to the Br2MO 3.Which statement is incorrect about the hydrogen halides? Correct Answer:For each HX,the pKa value is negative indicating that each is a strong acid 4.Match the shape to the formula.Which pairing is correct? Correct Answer:[BrF2];non-linear 5.Which reaction is not likely to occur? Correct Answer:ClF3+BF3[BF2][CIFa] 6.Which of the following oxides is paramagnetic? Correct Answer:ClO2 7.C1207 is the anhydride of: Correct Answer:HCIO 8.Which statement is incorrect about oxoacids of the halogens?
A. I2 + I- → [I3] - B. Cl2 + 2[OH]- → Cl- + [OCl]- + H2O C. Br- + 3[OCl]- → [BrO3 ]- + 3Cl- D. HOI + 2HCl → H+ + [ICl2] - + H2O 20. In which one of the following reactions is at least one iodine atom oxidized? A. IF5 + 2SbF5 → [IF4][Sb2F11] B. Cs[ICl2] → CsCl + ICl C. I2 + I- → [I3] - D. 2I2 + S2O6F2 → 2[I2][SO3F] ANSWERS: 1. Which of the following correctly describes the trends in values of Pauling electronegativities (χP) and ionic radii (rion)? Correct Answer: χP: F > Cl > Br > I; rion: F < Cl < Br < I 2. The Br–Br distance in crystalline Br2 is 227 pm, but in the solid state structure of Ph3PBr2 it is 312 pm. This is because: Correct Answer: lone pair electrons from PPh3 have been donated to the Br2 σ* MO 3. Which statement is incorrect about the hydrogen halides? Correct Answer: For each HX, the pKa value is negative indicating that each is a strong acid 4. Match the shape to the formula. Which pairing is correct? Correct Answer: [BrF2] + ; non-linear 5. Which reaction is not likely to occur? Correct Answer: ClF3 + BF3 → [BF2][ClF4] 6. Which of the following oxides is paramagnetic? Correct Answer: ClO2 7. Cl2O7 is the anhydride of: Correct Answer: HClO4 8. Which statement is incorrect about oxoacids of the halogens? 5