Arrange the following amines in decreasing order of \(pK_{b}\) values in aqueous solution:
(A) Phenylmethanamine
(B) N-Ethylethanamine
(C) N-methylaniline
(D) \(NH_{3}\)
Choose the correct answer from the options given below:

In the following reaction, identify the product D:
\(C _6 H _5 OH + Zn~ \text{dust} \rightarrow A\)
\(CH _3 Cl + {\text { anhy. } AlCl _3} \rightarrow B\)
\({K_2 Cr _2 O _7+ H _2 SO _4} \rightarrow C\)
\({ H _2 SO _4+ HNO _3} \rightarrow D\)

The cell \(Zn \left| Zn ^{2+}(1 M ) \| Cu ^{2+}(1 M )\right| Cu\) has \(E_{\text {cell }}^{\circ}=1.10 V\).
The cell is allowed to be completely discharged at 298 K .
The relative concentration of \(Zn ^{2+} / Cu ^{2+}\) is:

The correct shape \(\&\) hybridisation for \(XeF_2\) are:

Read the passage carefully and answer the questions
Biomolecules are the organic compounds present as an essential constituents of living organisms in different cells.The molecules are generally termed as macromolecules, which are carbohydrates, enzymes, nucleic acids, amino acids and proteins etc. Carbohydrates are classified as sugars and non-sugars include sucrose, glucose, fructose, starch and cellulose. Enzymes are coordinated with various chemical reactions in nucleic acid. Nucleic acids are found in living organisms made up of proteins and natural polymers. Two types that are generally found in biological systems are DNA and RNA nucleic acid. Amino acids are bifunctional groups of carboxyl and amino groups. Proteins are a class of biologically important compounds. They are crucial to virtually all processes in living systems. Some of them are hormones, which serve as chemical messengers that coordinatecertain biochemical activities.
Glucose when treated with Bromine water forms

Oxidation of acetaldehyde with \(SeO_2\) forms:

The rate of a chemical reaction doubled for every 10°C rise in temperature. If the temperature is raised by 50°C, the rate of reaction will be

The relation \(R=\{(a, b):\) both \(a\) and \(b\) are either odd or even \(\}\) on the set \(\{1,2,4,5,7,8\}\) is

Observe the illustration and answer the following question:

Which of the following is TRUE for spermatogenesis and oogenesis?
A. Spermatogenesis starts at puberty
B. Oogenesis starts at puberty
C. Two sperms are formed from one primary spermatocyte
D. One ovum is formed from one primary oocyte
Choose the most appropriate answer from the options given below:

A charged particle is moving in a cyclotron. What is the effect on time for one revolution of this charged particle, when its radius of the orbit is doubled?

Recombinant DNA technology involves the following steps in a specific sequence.
(A) Culture of the host cell
(B) Extraction of desired product
(C) Isolation of desired DNA fragments
(D) Transformation of the recombinant DNA into the host cell
Arrange these sequences correctly and choose the correct answer from the options given below:

Read the following passage carefully and answer the given questions.
Biofertilisers
Biofertilisers are organisms that enrich the nutrient quality of the soil and their main sources are bacteria, fungi and cyanobacteria. You have studied about the nodules on the roots of leguminous plants formed by the symbiotic association of Rhizobium. These bacteria can fix atmospheric nitrogen into organic forms. Other bacteria can also fix atmospheric nitrogen while free-living in the soil (examples Azospirillum and Azotobacter). Fungi are also known to form symbiotic associations with plants (mycorrhiza). Many members of the genus Glomus form mycorrhiza. Plants having such associations show other benefits also, such as resistance to root-borne pathogens, tolerance to salinity and drought, and an overall increase in plant growth and development. Cyanobacteria are autotrophic microbes widely distributed in aquatic and terrestrial environments many of which can fix atmospheric nitrogen, e.g. Anabaena, Nostoc, Oscillatoria, etc. In paddy fields, cyanobacteria serve as an important biofertiliser. Blue green algae also add organic matter in to the soil and increase its fertility. Currently, in our country, a number of biofertilisers are available commercially in the market and farmers use these regularly in their fields to replenish soil nutrients and to reduce dependence on chemical fertilisers.
Choose the free living, nitrogen-fixing bacteria from the following.

Read the given passage and answer the question given below.
The sex linked recessive disease, which shows its transmission from unaffected carrier female to some of the male progeny has been widely studied. In this disease, a single protein that is a part of the cascade of proteins involved in the clotting of blood is affected. Due to this in an affected individual a simple cut will result in non-stop bleeding. The heterozygous female (carrier) for the disease may transmit it to sons. The possibility of a female becoming a sufferer of disease is extremely rare because mother of such a female has to be at least carrier and the father should be sufferer. The family pedigree of Queen Victoria shows a number of suffering descendents as she was a carrier of the disease.
Man who is sufferer of the disease marries a woman who is a carrier of this disease. What percentage of children born as carrier of this disease?