In the form of dichromate, Cr(VI) is a strong oxidising agent in acidic medium but Mo (VI) in MoO3 and W (VI) in WO3 are not. Choose the correct reason from the options given below:
(A) Cr (VI) is more stable than Mo (VI) and W (VI)
(B) Mo (VI) and W (VI) are more stable than Cr (VI)
(C) Higher oxidation states of heavier members of group-6 of transition series are more stable
(D) Lower oxidation states of heavier members of group-6 of transition series are more stable
Choose the correct answer from the options given below:

Which of the following alkyl halide will undergo \(\mathrm{S}_{\mathrm{N}} 1\) reaction fastest?

Which of the following will NOT be coloured?

Read the passage carefully and answer the Questions
The term vitamin was coined from the word vital +amine since the earlier identified compounds had amino groups. Later work showed that most of them didn't contain amino groups, so the letter "e" was dropped and ther term vitamin is used these days.
Vitamins are classified into two groups depending upon their solubility in water or fat. Fat soluble vitamins are soluble in fat and oils but insoluble in water. They are stored in liver and adipose (fat storing) tissues. Water-soluble vitamins are soluble in water. They must be supplied regularly in the diet as they are readily excreated in urine.
What are the sources of Vitamin B12?

Answer the question on the basis of passage given below :
Strong oxidising agents oxidise toluene and its derivatives to benzoic acid. However, it is possible to stop the oxidation at the aldehyde stage with suitable reagents that convert the methyl group to an intermediate that is difficult to oxidise further.
Conversions that can be done by same reagent are:
(A) Benzaldehyde to 2-nitrobenzaldehyde
(B) Propan-1-ol to propanal
(C) Pent-3-en-2-ol to pent-3en-2-one
(D) Butanal to Butan-1-ol
(E) Methanal to Ethanol
Choose the correct answer from the options given below :

Which of the following is a fat soluble vitamin?

Match List - I with List - II.

List - I	List - II
(A) Oxidation of primary alcohol to Aldehyde	(I) Concentrated sulphuric acid
(B) Oxidations of primary alcohol to carboxylic acid	(II) Zn. dust
(C) Dehydration of propanol to propene	(III) \(CrO _3\) in anhydrous medium
(D) Phenol to benzene	(IV) Acidified potassium permanganate

Choose the correct answer from the options given below :

The figure shows a long cylindrical straight wire of radius a carrying steady current (I). The current (I) is uniformly distributed across the cross-section of the wire. The ratio of the magnetic fields at points \(r=\frac{a}{3}\) and \(r=\frac{a}{2^{\prime}}\) respectively is: Here r is the distance of point from the axis of cylinder.

Diodes are most commonly used for rectification of alternating voltages. This is because, in diode
(A) current flows in one direction only
(B) forward bias resistance is low as compared to reverse bias resistance
(C) reverse current is independent of the voltage applied
(D) reverse current is linearly dependent on the voltage applied
Choose the correct answer from the options given below:

Which contrasting trait was not considered by Mendel in pea plant?

Which one of the following regions is not present in transcriptional unit of DNA

Value of \(\int_2^3 \frac{\sqrt{x}}{\sqrt{x}+\sqrt{5-x}} d x\) is

An electron of mass \( 9.1 \times 10^{-31} \text{ kg} \) carrying charge \( 1.6 \times 10^{-19} \text{ C} \), is moving horizontally with a speed of \( 4 \times 10^6 \text{ m/s} \) in a uniform magnetic field of magnitude \( 8 \times 10^{-4} \text{ T} \) acting vertically upward. The radius of its circular path is,