The amount of radioactive substance left after \(75\) hours,
when \(100\) g of it is taken initially, will be:
(Half-life of the radioactive substance is \(15\) hours)

Answer the question on the basis of passage given below :
One of the notable features of the transition element is the great variety of oxidation states it may show in its compounds. The elements which give the greatest number of oxidation states occur in or near the middle of the series. Manganese, for example exhibits all the oxidation states from +2 to +7. The lesser number of oxidation states at the extreme ends is either due to losing or sharing of few electrons (Sc, Ti) or too many d electrons of higher valence. Early in the first series scandium (II) is virtually unknown and titanium (IV) which is more stable than Ti (III) or Ti (II). On the other end, the only oxidation state of zinc is \(+ 2\).
Cris reducing but Mn is oxidising in nature although both have \(d ^{ 1 }\) configuration. It is due to the reason that Cr configuration changes from

Arrange the following ions in increasing order of number of 3d-electrons
(A) Cr²⁺
(B) Cu⁺
(C) Ti³⁺
(D) Mn⁺
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Match List-l with List-II

List-l	List-II
A. \(CH _3 CHO \xrightarrow{773 K} CH _4+ CO\)	I. Zero order
B. \(2 NH _3 \xrightarrow{ Pt } N _2+3 H _2\)	II. Carbolic acid
C. \(H _2+ Br _2 \rightarrow 2 HBr\)	III. 1.5
D. \(SO _2 Cl _2 \rightarrow SO _2+ Cl _2\)	IV. First order

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The reaction of two molecules of 1-chlorobenzene with sodium metal in the presence of dry ether to form diphenyl is known as

Identify the incorrect statement
A. Bakelite and urea-formaldehyde resins are elastomers
B. Polyamides like nylon 6, nylon 6, 6 are the examples of fibers.
C. Polystyrene, polyvinylchloride and polythene are thermoplastic polymers.
D. Thermoplastic polymers have intermolecular force between elastomers and fibers.
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What is the correct IUPAC name of\([Pt(NH_{3})_{2}Cl_{2}]\)

Chronologically arrange the names of scientists who contributed to the study of genetics.
(A) Alfred Sturtevent
(B) Gregor Mendel
(C) Thomas Hunt Morgan
(D) Sutton and Boveri
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Increasing order of reducing power of following hydrides would be
A. SbH 3
B. AsH3
C. NH3
D. PH3
E. BiH3
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Signals of parturition originate from which of the following?
A. Human Placental Lactogen
B. Parturition hormone
C. Fully developed foetus
D. Placenta
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Which of the following is necessary to use to achieve half wave rectification of an alternating current?

A function \(f:[0,2] \rightarrow R\) is strictly increasing in \([0,1]\) and strictly decreasing in \([1,2]\). Then which statement is TRUE?

\(\int\left(e^{x \log a}+e^{a \log x}\right) d x\) is equal to (where \(\left.a>1\right)\)