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Compound X decolourises acidified potassium dichromate to produce an acid with a pH value of 4.5. Which of the following could be the structure of X?

ACH₃CH₂COOH
BCH₃CH₂CH₂OH
CCH₂CHCH₃
DCH₃CH₂CH₃

A coordinate axis as shown in figure is kept in front of a converging lens at a distance 2f from it, where f is the focal length of the lens.
Which of the following shows the approximate shape of the image? Assume that X-axis is the principal axis of the lens.



A

B

C

D

What is X and Y in the given rhyme about a traffic signal?


A
B
C
D

Rahul is travelling in a bus moving at a constant speed of 50 km h^-1. At one point of his journey, he throws a ball vertically upwards to a height 40 cm, the ball will fall (Neglect air friction)

A A short distance behind where he is standing
B A long distance in front of where he is standing
C A long distance behind where he is standing
D At the same spot where he is standing.

Study the given classification chart and select the correct option.

    
              a                  b             c               d

ANylon         Cotton       Silk          Wool
BFlax            Silk           Cotton       Wool
CCotton         Flax          Wool         Silk
DCotton         Jute           Silk           Wool

The given figure shows the set-up to study the reaction between gas X and copper (II) oxide :

Which of the following statements are correct?
[Given : Atomic mass of N = 14 u, H = 1 u, O = 16 u, C = 12 u]
I. Gas X is a compound of two elements, nitrogen and hydrogen.
II. The number of atoms present in 11.2 L of N₂ is 6.023 × 10²³.
III. 1 mole of H₂O contains 1 mole of oxygen molecules and 2 moles of hydrogen atoms.
IV. N₂ gas being soluble in water is collected by upward displacement of water.

AI and II only
BI and III only
CII and IV only
DIII and IV only

If White is called Black, Black is called Red, Red is called Green and Green is called Yellow, then colour of the human blood is _________.

AGreen
BWhite
CYellow
DBlack

To demagnetise a magnet using the heating method, which of the following is the correct step?

AHeat the magnet to become red hot, and allow it to cool in the east west direction.
BHeat the magnet to become red hot, and allow it to cool in the north south direction.
CHeat the magnet in boiling water, and allow it to cool in the north south direction.
DBoth A and B

________ is the organ where absorption of water from undigested food occurs.

A
B
C
D

Which of the following options will complete the pattern in Fig. (X)?
    


A

B

C

D