Formaldehyde undergoes the Cannizzaro reaction because:
(A) It has alpha-hydrogen atom.
(B) It does not have alpha-hydrogen atom.
(C) It does not undergo self-oxidation and reduction on heating with concentrated alkali.
(D) It undergoes self-oxidation and reduction on heating with concentrated alkali.
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Which is the correct IUPAC name of the compound \(CH _3 CH = CHC ( Br )\left( CH _3\right)_2 ?\)

Answer the question on basis of passage given below :
A ketone \([A]\) which undergoes haloform reaction gives compound \([B]\) on reduction. Compound \([B]\) on heating with sulphuric acid gives compound \([C]\) which forms monozonide \([D]\). The compound [D] on hydrolysis in the presence of zinc dust gives compound [E].
Compound [E] on oxidation gives \(C _2 H _4 O _2\) [F]
The boiling point of \([ A ]\) observed is exceptionally high because of :

Which phenomenon occurs when an electric field is applied to a colloidal solution and electrophoresis is prevented?
(A) \quad Reverse osmosis takes place
(B) \quad Electroosmosis takes place
(C) \quad Dispersion medium begins to move in an electric field
(D) \quad Dispersion medium becomes stationary
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Match the elements given in List-I with electronic configuration given in List-II

List - I (Element)	List - II (Electronic configuration)
(A) Cerium	(I) \([ Xe ] 4 f^{f 12} 6 s^2\)
(B) Erbium	(II) \([ Rn ] 5 f^7 6 d^1 7 s^2\)
(C) Uranium	(III) \([ Xe ] 4 f^1 5 d^1 6 s^2\)
(D) Curium	(IV) \([ Rn ] 5 f^3 6 d^1 7 s^2\)

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Which of the following sols are correctly matched with their corresponding charges ?
(A) \(\text{Cr(OH)}_3\) sol : negatively charged sol
(B) \(\text{TiO}_2\) sol : positively charged sol
(C) \(\text{CdS}\) sol: positively charged sol
(D) Gum: negatively charged sol
(E) Silver sol : positively charged sol
Choose the correct answer from the options given below :

Answer the question on the basis of passage given below :
For the transition elements
Sc \(\quad\) Ti \(\quad\) V \(\quad\) Cr \(\quad\) Mn\(\quad\) Fe \(\quad\) Co \(\quad\) Ni \(\quad\) Cu \(\quad\) Zn
Atomic numbers :
21 \(\quad\) 22 \(\quad\) 23 \(\quad\) 24 \(\quad\) 25 \(\quad\) 26 \(\quad\) 27 \(\quad\) 28 \(\quad\) 29 \(\quad\) 30 \(\quad\)
Which transition element ion \(\text{M}^{3+}\) has electronic configuration \(3d^5 4s^0\)?

Read the passage carefully and answer the questions:
The degeneracy of the \(d\) orbitals has been removed due to ligand electron-metal electron repulsions in the octahedral complex to yield three orbitals of lower energy, \(t_2\), set and two orbitals of higher energy, \(e_g\) set. This splitting of the degenerate levels due to the presence of ligands in a definite geometry is termed as crystal field splitting and the energy separation is denoted by \(\Delta_0\). Thus energy of the two \(e_g\), orbitals will increase by \((3 / 5) \Delta_0\) and that of three \(t_{2 g}\) will decrease by \((2 / 5) \Delta_0\). The crystal field splitting \(\Delta_0\) depends upon the field produced by the ligand and charge on the metal ion. Some ligands are able to produce strong fields, in which case the splitting will be large, whereas others produce weak fields and consequently result in small splitting of \(d\) orbitals. Relative magnitude of crystal field splitting energy \(\Delta_0\) and pairing energy, \(P\) (energy required for electron pairing in a single orbital) determine the formation of low spin ( \(\Delta_0>P\) ) or high spin ( \(\Delta_0<P\) ) complex. In tetrahedral coordination entity formation, the \(d\)-orbital splitting is inverted and is smaller as compared to the octahedral field splitting. The crystal field theory attributes the colour of the complex to \(d-d\) transition of the electron. The colour of the coordination compounds depends on the crystal field splitting. In the absence of ligand, crystal field splitting does not occur and hence the substance is colourless.
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The value of b , for which the function \(f(x)= \begin{cases} 5x - 4, & 0 < x \leq 1 \\ 4x^2 + 3bx, & 1 < x < 2 \end{cases}\), is continuous at every point of its domain is :

C, Si and Ge have the same lattice structure but C is an insulator while Si and Ge are intrinsic semiconductors because
(A) ionisation energy will be least for C, followed by Si and highest for Ge
(B) ionisation energy will be least for Ge, followed by Si and highest for C
(C) number of free electrons for conduction in Ge and Si are negligibly small but significant for C
(D) number of free electrons for conduction in Ge and Si are significant but negligibly small for C
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Arrange the given structures starting from chalazal end to micropylar end in a mature embryo sac?
(A) Central cell
(B) Antipodals
(C) Synergids
(D) Egg
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Microbes in human welfare Microbes are a very important component of life on earth. we use microbes and microbially derived products almost every day, like LAB to make curd, yeast to make bread, adding flavor and texture to cheese, producing antibiotics etc. The addition of LAB, improves the milk quality by increasing vit. B12. Cheese is one of the oldest food items in which microbes are used. For example, large holes in Swiss cheese are due to CO2 produced by the bacterium Propionibacterium sharmanii. The BOD test measures the rate of uptake of oxygen by microorganisms in a sample of water and thus, indirectly, BOD is a measure of the organic matter present in the water. The greater the BOD of waste water, the more is its polluting potential. In anaerobic sludge digesters, bacteria produce a mixture of gases like methane, hydrogen sulphide and carbon dioxide. These gases form biogas and can be used as a source of energy. Biofertilisers are organisms that enrich the nutrient quality of the soil. The main sources of biofertilisers 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 fix atmospheric nitrogen into organic forms, which is used by the plant as a nutrient. Other bacteria can fix atmospheric nitrogen while free-living in the soil (examples Azospirillum and Azotobacter).
The large holes in Swiss cheese are generated by-

Roman numbers in the names of restriction enzymes indicate -