Important Paper BCECE

Q1. A gas is found to have a formula [CO] x . Its vapour density is 70, the x is

1. 3.0
2. 3.5
3. 5.0
4. 6.5

Answer: C

Q2. Which of the following is used as purgative?

1. HgS
2. Hg 2 Cl 2
3. HgCl 2
4. ZnSO 4

Answer: B

Q3. Least stable oxide of chlorine is

1. Cl 2 O
2. ClO 2
3. Cl 2 O 7
4. ClO 3

Answer: A

Q4. The sides of safety matches contains

1. red phosphorus + sand powder
2. P 4 S 3
3. Ca 3 (PO) 4 + glass pieces
4. KCIO 3 , KNO 3 , sulphur + antimony

Answer: A

Q5. Chemically aspirin is known as

1. salicylic acid
2. salicylaldehyde
3. 2-acetoxybenzoic acid
4. phenyl salicylate

Answer: C

Q6. If forces of magnitude 12 kg-wt, S kg-wt and 13 kg-wt act at a point are in equilibrium, then the angle between the first two forces is

1. 30°
2. 90°
3. 60°
4. 45°

Answer: B

Q7. On one bank of river there is a tree. On another bank, an observer makes an angle of elevation of 60° at the top of the tree. The angle of elevation of the top of the tree at a distance 20 m away from the bank is 30°. The width of the river is

1. 20 m
2. 10 m
3. 5 m
4. 1 m

Answer: B

Q8. Let a, b, c be positive and not all equal, the a b c value of the determinant

1. +ve
2. –ve
3. zero
4. none of these

Answer: B

Q9. A body is projected at such angle that the horizontal range is three times the greatest height. The angle of projection is

1. 42°8'
2. 53°7'
3. 33°7'
4. 25°8'

Answer: B

Q10. A particle moving with a uniform acceleration travels 24 m and 64 m in the first two consecutive interval of 4 s each. Its initial velocity will be

1. 5 m/s
2. 3 m/s
3. 1 m/s
4. 4 m/s

Answer: C