Groups with +M effect increase the electron density of the rest of the molecule
eg `Cl, -Br, -I, -NH_(2), NHR, NR_(2), -OH,-OR, -OCOR, -NHCOR` etc

Groups with -M effect decrease the electron density of the rest of the molecule eg- -COOH, -COOR, -CHO, -COR, -CO-, -CN, -NO_(2), -SO_(3)H etc

Consider the following groups attached to benzene ring and how many of these show -"I" effect only - NH_2, - NH_3, - F, - CH_2OH, - CH_3, - NHCOR, -OCH_3, - OH

Which bond is more polar in the following pairs of molecules: (a) H_(3)C-H, H_(3)C-Br (b) H_(3)C-NH_(2), H_(3)C-OH (c ) H_(3)C-OH , H_(3)C-SH

Identify the atoms or groups from the following that exhibit - R effect and +R effect when present on benzene ring : -OR, - "NHCOR", - "CN", - "X", - "NO"_(2), - "NH"_(2) ,

Which bond is more polar in the following pairs of molecules: (i) H_(3)C- H, H_(3)C- Cl (ii) H_(3)C- OH, H_(3)C-NH_(2) (iii) H_(3)C- SH, H_(3)C-OH

Arrange the following in the order of the property indicated for each set. F_(2),Cl_(2),Br_(2),I_(2) - increasing bond dissociation enthalpy.

Give the correct increasing order of electrical conductivity of aqueous solutions of following complex entities I) [Pt(NH_3)_6]Cl_4 II) [Cr(NH_3)_6]Cl_3 III) [Co(NH_3)_4Cl_2]Cl IV) K_2 [ PtCl_6]

PASSAGE - 3 : In modern periodic table there is gradation in the properties of elements. In a period the Ionisation energy, Electron affinity, Electro negativity, Non-Metallic nature increases. In a group the atomic size, metallic nature, reducing properties and densities of elements increases. In the compunds KO_2,Cr_2,O_3,SO_2 and Cl_2O_3 Which element shows more valency with respect to oxygen

Only the surface atoms in an adsorbent, play an active role in adsorption. These atoms posses some residual forces like vander Waal's forces and chemical forces. In the process of adsorption, weak adsorbate is substituted by strong adsorbate. Activated charcoal used in gas mask is already exposed to the atmospheric air, so the gases and water vapours in air are adsorbed on its surface. When the mask is exposed to chlorine atmosphere, the gases are displaced by chlorine. Porous and finely powdered solids, e.g., charcoal and Fuller's earth adsorb more as compared to the hard non-porous material. It is due to this property that the powdered characoal is used in gas masks. In general, easily liquefiable gases like CO_2, NH_3, Cl_2 , and SO_2 etc., are adsorbed to a greater extent than the elemental gases, eg., H_2, N_2, O_2, He , etc. Which of the following gases will substitute O_2 from adsorbed charcoal

Only the surface atoms in an adsorbent, play an active role in adsorption. These atoms posses some residual forces like vander Waal's forces and chemical forces. In the process of adsorption, weak adsorbate is substituted by strong adsorbate. Activated charcoal used in gas mask is already exposed to the atmospheric air, so the gases and water vapours in air are adsorbed on its surface. When the mask is exposed to chlorine atmosphere, the gases are displaced by chlorine. Porous and finely powdered solids, e.g., charcoal and Fuller's earth adsorb more as compared to the hard non-porous material. It is due to this property that the powdered characoal is used in gas masks. In general, easily liquefiable gases like CO_2, NH_3, Cl_2 , and SO_2 etc., are adsorbed to a greater extent than the elemental gases, eg., H_2, N_2, O_2, He , etc. Which of the following gases will be most easily adsorbed by the charcoal in the gas mask