1 )
An amount of water of mass 20 g at 0 C ( Celsius ) is mixed with 40 g of water
at 10 C . Final temperature of mixture is : -
A ) 10 C , B
) 40 C ,
C ) 273 C , D
) None of these ,
Correct
Answer : - B ) 40 C ,
Solution
: -
. .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 )
If the molecule of HCL is totally polar , the observed value of dipole moment
is 1.03 D but the experimental value of dipole moment was 6.12 D . Calculate
the percentage of ionic character ?
A ) 1.3 % , B
) 17 % ,
C ) 71 % , D
) None of these ,
Correct
Answer : - B ) 17 % ,
Solution
: -
Dipole moment is the difference in electronegativity of
two atoms of a molecule .
µ = 0 , ( For non – polar ) And µ
≠ 0 , ( For polar ) .
So ,
Ionic character
= ( Observed / Calculated ) x 100
,
Ionic character
= ( 1.03 D / 6.12 D ) x 100 ,
Ionic
character = 17 %
, Answer .
. .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 )
Calculate the percentage of covalent character of HX having bond length = 1.62
A and observed dipole moment = 0.39 D ?
A ) 1.3 % , B
) 17 % ,
C ) 95 % , D ) None of these ,
Correct
Answer : - C ) 95 % ,
Solution : -
. .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
