Page 51 - Fpgee Question And Answer 2024 Edition
P. 51

www.pharmacyexam.com                                                                  Krisman

            P  = 790 mm Hg                                        V = Volume in liter = 200/1000 = 0.2L
             1
            V  = 200 ml                                                                 W     Weight in gram
             1
                    o
                                o
            T  = 303   K (273 + 30  C)                            n = Number of moles =   M  =  Molecular weight
             1
            P  = 860 mm Hg                                                           o
             2
            V  = ?                                                T = Temperature in K = 100 + 273 = 373
             2
                                                                  R = Gas constant = 0.08205 lit atm/ mole degK
                    o
                                o
            T  = 313   K (273 + 40  C)
             2
                                                                  PV = nRT
                 P  x V  x T
            V =    1  1   2                                           W
             2
                   P  x T 1                                       PV =  RT
                    2
                                                                      M

                 790 x 200 x 313                                      WRT
            V =                                                   PV =
             2
                    860 x 303                                          M

                                                                      WRT   0.30 x 0.082 x 373
            V = 189.78 ml                                         M =   PV   =    1 x 0.2   = 46 grams/mole
             2

            1234. (a) The ideal gas Law equation is described as   1236. (c) The number of moles of solute in 1000 cc
            follows:                                              of  solution  is  defined  as  molarity.  Therefore,  1M
                                                                  CaCO   solution  should  contain  88  grams  (since  1
            PV = nRT where,                                            3
                                                                  mole of CaCO  = 88 grams/mole) CaCO in 1000 cc
                                                                              3                       3
            P = Pressure (atm)                                    of solution.

            V = Volume (liter)
            n = Number of moles of gas                            1000 cc 1M solution requires    88 gm CaCO
                                                                                                         3
                             o
            T = Temperature in  K                                 250 cc 1M solution requires       ?
                                     o
            R = 0.0821 lit x atm/ mole x  K                         250 x 88
                                                                   1000    = 22 grams CaCO
                                                                                           3
            At Standard Temperature and Pressure (STP),
                                                                  1237. (c) The equivalent weight of the molecule can
            P = 1 Atm pressure                                    be calculated by using the following formula:
                  o
            T = 273 K
            n = 1 mole                                            Equivalent weight =   Molecular weight
                                                                                      Number of valence
                 n R T
            V  =                                                  Equivalent weight =  106  = 53 gm/Eq
                   P                                                                   2

                 1 x 0.0821 x 273                                 The equivalent weight of Na 2CO 3 is numerically half
            V  =
                        1                                         of  its  molecular  weight.  The  valence  of  carbonate
                                                                  ion, CO 3 , is 2 and its equivalent weight is 60/2 = 30
                                                                         -2
            V  =  22.414 liters                                   gm/Eq.  Although  the  valence  of  Na  is  unity,  two
                                                                  atoms are present in Na 2CO 3, providing a weight of
            1235. (d)  The  ideal  gas  Law  is  described  by  the   2  x  23  gm  =  46gm;  hence  its  equivalent  weight  is
            following equation:                                   one  half  of  this  or  46/2  =  23  g/Eq.  Thus  the
                                                                  equivalent weight of Na 2CO 3 is 30 + 23 = 53 gm.
            PV = nRT where,
                                                                  1238. (a) The equivalent weight of the atom can be
            P = Pressure in atm = 1                               calculated by using the following formula:

                                                             320
   46   47   48   49   50   51   52   53   54   55