To avoid the medical condition called 'bends' in scuba divers, the composition of gas filled in the tank is

The synthesis of Alkyl fluoride is best carried through :

Read the passage carefully and answer the questions
Ethers with the general formula \(C _n H _{2 n+2} O\) and functional group C-O-C may be divided as symmetrical and unsymmetrical.
Lower symmetrical ether may be obtained by the dehydration of alcohols at low temperatures in the presence of protic acids,
such as \(H _2 SO _4\) and \(H _3 PO _4\) whereas at high temperature intramolecular dehydration takes place.
Formation of ether from primary alcohols is also accompanied by the formation of small amount of alkenes.
Due to the steric hinderance, secondary and tertiary alcohols undergo elimination reaction rather than substitution reaction yielding alkene as major product. Ethers can also be obtained by heating alkyl halides with sodium or potassium alkoxides.
Substituted Ethers (secondary & tertiary) can also be prepared using this method.
If primary halides are replaced with secondary and tertiary halides, alkenes are the major products. The compound with the lowest boiling point is

The chemical formula of Magnetite is :

The unit of Boiling point Elevation Constant (\(K_b\)) is

Identify the order of reaction if its rate constant is \(k = 2 \times 1 0 ^{- 2 } s ^{- 1 }\) :

Match List-l with List-II

List-I	List-II
(A) Kolbe's reaction	(I) Preparation of symmetrical and unsymmetrical ethers
(B) Williamson synthesis	(II) Preparation of Salicylic acid
(C) Lucas test	(III) Organo-Magnesium halide
(D) Grignard's reagent	(IV) Distinction between different types of alcohols

Choose the correct answer from the options given below:

The equation of plane which cuts equal intercepts of unit length on the coordinate axes is:

Which of the following phenomenon is responsible for the reddish appearance of sun during sunset or sunrise ?

Which of the following argument supports the conservation of biodiversity
from the below statement:
"Waking up to a Bulbul's song in the morning"

Which of the region shown in the given figures represents the feasible region bounded by the following constraint?
\(4 x+y \geq 80,2 x+y \geq 60, x+y \leq 80, x \geq 0, y \geq 0\)

Arrange the given steps of decomposition cycle in a terrestrial ecosystem in correct sequence?
(A) Bacterial and fungal enzymes degrade detritus into simpler a inorganic substances and its catabolism.
(B) Earthworms break-down detritus into smaller particles and is called fragmentation.
(C) Leaching - water soluble inorganic nutrients go down into the soil horizon.
(D) Microbes release inorganic nutrients in the soil and it is called mineralisation.
Choose the correct answer from the options given below:

A white light falls on a prism. Among given choices which light bends the least?