Chemistry Study Material

1.Which of the following readicals have pyramidal shape (I) CH3 (II) CF3 (III) CD3 (IV) ⧊ (a) I, II (b) I, II, IV (c) III, IV (d) II and IV 2. Spin trapping technique is used for detection of (a) carbonium ion (b) Free radical (c) Benzyne (d) Carbanion 3.Correct order of stability of free radicals (I-IV) is (I) H2C CH CH2 • (II) Me2CH • (III) Ph • (IV) Ph3C • (a) I > IV > II > III (b) IV > I > III > II (c) IV > III > I > II (d) IV > I > II > III

Oxyacid , any oxygen -containing acid . Most covalent nonmetallic oxides react with water to form acidic oxides; that is, they react with water to form oxyacids that yield hydronium ions (H 3 O + ) in solution. There are some exceptions, such as carbon monoxide , CO, nitrous oxide , N 2 O, and nitric oxide , NO. The strength of an oxyacid is defined by the extent to which it dissociates in water (i.e., its ability to form H + ions). In general, the relative strength of oxyacids can be predicted on the basis of the electronegativity and oxidation number of the central nonmetal atom . The acid strength increases as the electronegativity of the central atom increases. For example, because the electronegativity of chlorine (Cl) is greater than that of sulfur (S), which is in turn greater than that of phosphorus (P), it can be predicted that perchloric acid, HClO 4 , is a stronger acid than sulfuric acid , H 2 SO 4 , which should be a stronger acid than phosphoric acid , H 3