NARAYANA IIT ACADEMY JEE MAIN – 2013 - Narayana Group

(1) Methylisocyanate (2) Methylamine (3) Ammonia (4) Phosgene
Key : 1
Sol: (1)
MIC was responsible for Bhopal gas tragedy.
60. Experimentally it was found that a metal oxide has formula M
0.98
O . Metal M, is present as
2
M and
3
M
3
M
in its oxide. Fraction of the metal which exists as would be
(1) 7.01 % (2) 4.08 % (3) 6.05% (4) 5.08 %
Key : 2
Sol: (2)
3
Let the number of M and
x y 0.98 ….(i)
3x
2y
2 ….(ii)
3
No. of M ion = 0.04
2
And M ion = 0.94
So percentage of
2
M ions be x and y respectively
3
M ion 0.04 100 4.08%
0.98
MATHEMATICS
61. Distance between two parallel planes 2x + y + 2z = 8 and 4x + 2y + 4z + 5 = 0 is
(1) 3 2
(2) 5 2
(3) 7 2
(4) 9 2
Key. (3)
Sol: Required distance =
5
8
2 7
2 2 2
2 1 2 2
62. At present, a firm is manufacturing 2000 items. It is estimated that the rate of change of
dP
production P w.r.t. additional number of workers x is given by 100 12
dx
x.
If firm
employs 25 more workers, then the new level of production of items is
(1) 2500 (2) 3000 (3) 3500 (4) 4500
Key. (3)
Sol: (100 12 x)
dx
dp
24 3/2
100x x P C
3
when x = 0 P = 2000
P = 2000 + 100 x -
As x is 25
P = 3500
24
3 x
3/2
NARAYANA IIT ACADEMY JEE MAIN – 2013