1. Identify the wrong statement in the following (AIEEE 2008).
A. CFCs are responsible for ozone layer depletion.
B. Greenhouse effect is responsible for global warming.
C. Ozone layer does not permit I.R. radiation from the sun to reach the earth.
D. Acid rain is mostly because of oxides of ‘N’ and ‘S’.
Answer : Option C
2. In the reaction
A. 6L
B. 33.6L
C. 67.2L
D. 11.2L
Answer : Option D
3. Consider a titration of potassium dichromate solution with acidified Mohr’s salt solution using diphenyl amine as indicator. The number of moles of Mohr’s salt required per mole of dichromate is (IIT JEE 2007)
A. 3
B. 4
C. 5
D. 6
Answer : Option D
Explanation :
The redox reaction between potassiumdichromate and Mohr’s salt is :
4. Which has maximum number of atoms ? (IIT JEE 2003)
A. 24g of C (12)
B. 56g of Fe(56)
C. 27g of Al (27)
D. 108g of Ag (108)
Answer : Option A
Explanation :
Number of particles
5. What volume of hydrogen gas at 273K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) form the reduction of boron trichloride by hydrogen (AIEEE 2003)
6. In an organic compound of molar mass 108 g/mol, C,H and N atoms are present in 9:1:3.5 by weight Molecular formula can be (AIEEE 2002)
A.
B.
C.
D.
Answer : Option A
Explanation :
mass of carbon =
similarly, no of H and N atoms are 8 and 2 respectively.
7. Number of atoms in 560 g of Fe (atomic mass = 56) is (AIEEE 2002)
A. Twice that of 70 g N.
B. Half that of 20 g H
C. Both A and B
D. None of these
Answer : Option C
8. In the standardization of
A.
B.
C.
D. Same as molar mass
Answer : Option B
Explanation :
During the reaction,
Mixture X=0.02 mole of
1L of mixture X + excess
1L of mixture X + excess
Number of mole of Y and Z are (IIT JEE 2003)
A. 0.01, 0.01
B. 0.02, 0.01
C. 0.01,0.02
D. 0.02, 0.02
Answer : Option A
Explanation :
In 2L solution, there are 0.02 mol
Hence, Y= 0.01 mol AgBr
Z= 0.01 mol
10. How many moles of electron weight one kilogram ? (IIT JEE 2002)
A.
B.
C.
D.
Answer : Option D
Explanation :
Mass of an electron
No of electron's in 1 Kg