Ans: XeF6 + 2H2O + 4HF XeO2F2 Why has it been difficult to study the chemistry of radon? 49. Ans: Radon is radioactive with very short half-life which makes the study of Chemistry of radon difficult. 50. Halogens have maximum negative electron gain enthalpy in the respective periods of the periodic table. Why? Ans: Halogens have maximum negative electron gain enthalpy in the corresponding periods. This is due to the fact that the atoms of these elements have only one electron less than stable noble gas configurations. 51. AgCl is soluble in water, where as it is soluble in aqueous ammonia solution. Ans: Ammonia react with AgCl forms [Ag(NH3)2]Cl complex which is soluble in water. 52. Give the reason for bleaching action of Cl2. Ans: Chlorine water on standing loses its yellow colour due to the formation of HCl and HOCl. Hypochlorous acid (HOCl) so formed, gives nascent oxygen which is responsible for oxidising and bleaching properties of chlorine. 53. Why does the reactivity of nitrogen differ from phosphorus? Ans: Nitrogen can form multiple bonds and has more bond dissociation energy due to which it is less reactive. Phosphorous can not form multiple bonds. 54. Why does NH3 form hydrogen bond but PH3 does not? Ans: Electronegetivity of N is more than P. 55. The HNH angle value is higher than HPH, HAsH and HSbH angles. Why? Ans: Due to more electronegative nature of Nitrogen it causes more repulsion, hence bond angle is more.
Ans: XeF6 + 2H2O XeO2F2 + 4HF 49. Why has it been difficult to study the chemistry of radon? Ans: Radon is radioactive with very short half-life which makes the study of Chemistry of radon difficult. 50. Halogens have maximum negative electron gain enthalpy in the respective periods of the periodic table. Why? Ans: Halogens have maximum negative electron gain enthalpy in the corresponding periods. This is due to the fact that the atoms of these elements have only one electron less than stable noble gas configurations. 51. AgCl is soluble in water, where as it is soluble in aqueous ammonia solution. Ans: Ammonia react with AgCl forms [Ag(NH3)2]Cl complex which is soluble in water. 52. Give the reason for bleaching action of Cl2. Ans: Chlorine water on standing loses its yellow colour due to the formation of HCl and HOCl. Hypochlorous acid (HOCl) so formed, gives nascent oxygen which is responsible for oxidising and bleaching properties of chlorine. 53. Why does the reactivity of nitrogen differ from phosphorus? Ans: Nitrogen can form multiple bonds and has more bond dissociation energy due to which it is less reactive. Phosphorous can not form multiple bonds. 54. Why does NH3 form hydrogen bond but PH3 does not? Ans: Electronegetivity of N is more than P. 55. The HNH angle value is higher than HPH, HAsH and HSbH angles. Why? Ans: Due to more electronegative nature of Nitrogen it causes more repulsion, hence bond angle is more.
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