Formatting page ...
PRE BOARD EXAMINATION 2018 CLASS 12 CHEMISTRY - PAPER 1 (Theory) F.M. : 70 Time : 3hrs All questions are compulsory Question 1 is of 20 marks having 4 sub parts, all of which are compulsory . Question No. 2 - 8 carry two marks each, with any 2 questions having internal choice . Question No. 9 - 15 carry 3 marks each, with any two questions having an internal choice . Question No. 16-18 carry 5 marks each, with an internal choice. Gag Const. R= 1.987cal deg 1 mo1 1 = 8.314 Jk 1 mo1 1 = 0.0821 dm 3atm K 1 mo1 1 H'atm=ldm 3atm = 101.3J, lF =96500 coulombs, Avogardro's no.= 6.023 x 1023 Question 1 , ~ Fill in the blanks by choosing the appropriate word/words from those given in the brackets : . . . i [Cannizaro's, Kolbe's, Gattermann, 2, 4, 6 - tribromophenol, Pyrene, Gammexane, 2,4,6 - tnnitrophenol, acid c, neutral,!, basic, electron pair, bond pair electron, lone pair of electron, Ammonium cyanide, Methyl cyanide, e,e..,!O(" , f 1..,,_cfN. Potassium Cyanide, aldolB -iwil:lov ~eparation of chlorobenzene from Benzene diazonium chloride and aqueous HCI is known as ............................ . reaction. ~cric acid is ..................... .. ~ e r s behave as weakly .................................... substances because of the presence of ........................... Of - e~rons on oxygen atom. JM1ienzaldehyde when treated with an alcoholic solution of ........................ forms ................................. . [1+1+ + + + =41 J9( Match the following : ~odegradable polymer (a) a - ami no acid ,(ij)Y-Giycosidic linkage (b) Sucrose @j)afsaccharide (c) Lactose (~ten ion (d) PHBV [41 (c) Complete the following statement by selecting the correct alternative from the choices given : ~ e half-life period of a l't order reaction is 20min. The time required for the concentration of the reacta nt to change from 0.16 M ~.02M is : (1) 80 min . ~ min (3) 40 min (4) 20 min ~ c e centred cubic lattice, atom(A) occupies the corner positions and atom (B) occupies the face centre positions. If one atom of (B) is missing from one of the face centred points, the formula of the compounds is: ~ 1 ) AzBs (2) A283 (3) AB2 (4) Az B ~ r a spontaneous reaction t:.G 0 and Egel! will be respectively : (1) -ve and +ve (2) +ve and -ve ~ 2 ) +ve and +ve (4)-ve and --ve ~..................... is an outer orbital complex (1) [Fe(CN) 6 ] 4 (3) [Co(NH3) 6]3+ (2) [Mn (CN) 6 ) 4 (4) [Ni(NH3)6]2+ l41 (d) Answer the following questions: ~~ hy is the freezing point depression (t:.T1) of 0.4M NaCl nearly twice that of 0.4M glucose solution? ( (ii~ Name the order of reaction which proceeds with a uniform rate throughout. .re ecific conductivity of 0.2m solution of KCI at 298 K is 0.025 Scm 1 . Calculate its molar conductivity. ~ f i n d Raoult's law for the elevation of boiling point of a solution . the IUPAC name of the complex (Cr(NH3) 4 Cl2J+ . What type of isomerism will be exhibited by it? ~ e two main points of difference between lyophilic and lyophobic solutions. l81 Question 2 (a) A a.is M aqueous solution of KCI exerts an osmotic pressure of 6.8atm. at 310 K. Calculate the degree of dissociation of KCI. ... / OR WA 10% aqueous solution of cane sugar (M.W=342) is isotonic with 1.754% aqueous solution of urea. molecular mass of urea. Hnd the l21 .J/u'estion 3 ~ t two major classes of antibiotics. ~ the role of Aspirin . l21 ., ,- 2-
|
