7.1 Discuss the general characteristics of Group 15 elements with reference to their electronic configuration, oxidation state, atomic size, ionisation enthalpy and electronegativity.
7.2 Why does the reactivity of nitrogen differ from phosphorus?
7.3 Discuss the trends in chemical reactivity of group 15 elements.
7.4 Why does NH3 form hydrogen bond but PH3 does not?
7.5 How is nitrogen prepared in the laboratory? Write the chemical equations of the reactions . involved.
7.6 How is ammonia manufactured industrially?
7.7 Illustrate how copper metal can give different products on reaction with HN03.
7.8 Give the resonating structures of N02 and N2O5.
7.9 The HNH angle value is higher than HPH, H AsH and HSbH angles. Why?
7.10 Why does R3P = O exist but R3N = O does not (R = alkyl group)?
7.11 Explain why NH3 is basic while BiH3 is only feebly basic.
7.12 Nitrogen exists as diatomic molecule and phosphorus as P4. Why?
7.13 Write main differences between the properties of white phosphorus and red phosphorus.
7.14 Why does nitrogen show catenation properties less than phosphorus?
7.15 Give the disproportionation reaction of H3 P03 .
7.16 Can PCl5 act as an oxidising as well as a reducing agent Justify.
7.17 Justify the placement of O, S, Se, Te and Po in the same group’of the periodic table in terms of electronic configuration, oxidation state and hydride formation.
7.18 Why is dioxygen a gas but sulphur a solid?
7.19 Knowing the electron gain enthalpy values of O—>O– and O—>O2- as -141 and 702 kJ mol-1 respectively, how can you account for [he formation of a large number of oxides having O2- species and not O–?
7.20 Which aerosols deplete ozone?
7.21 Describe the manufacture of H2SO4 by contact process?
7.22 How is SO2 an air pollutant?
7.23 Why are halogens strong oxidising agents?
7.24 Explain why fluorine forms only one oxoacid, HOF.
7.25 Explain why inspite of nearly the same electronegativity, nitrogen forms hydrogen bonding while chlorine does not.
7.26 Write two uses of ClO2
7.27 Why are halogens coloured?
7.28 Write the reactions of F2 and Cl2 with water.
7.29 How can-you prepare Cl2 from HCl and HCl from CI2? Write reactions only.
7.30 What inspired N. Bartlett for carrying out reaction between Xe and PtF6?
7.31 What are the oxidation states of phosphorus in the following: –
7.32 Write balanced equations for the following:
7.33 How are xenon fluorides XeF2, XeF4 and XeF6 obtained?
7.34 With what neutral molecule is CIO– isoelectronic? Is that molecule a Lewis base?
7.35 How are XeO3 and XeOF4prepared?
7.36 Arrange the following in the order of property indicated for each set: –
7.37 Which one of the following does not exist ?
7.38 Give the formula and describe the structure of a noble gas species which is isostructural with: (i) ICI4– (ii) IBr2– (iii) Br03–
7.39 Why do noble gases have comparatively large atomic sizes?
7.40 List the uses of neoirand argon gases.