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It is observed that characteristic X-ray spectra of elements show regularity. When frequency to the power 'n' i.e. $$\nu^n$$ of X-rays emitted is plotted against atomic number Z, the following graph is obtained.
The value of 'n' is
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Decreasing order of the hydrogen bonding in following forms of water is correctly represented by
A. Liquid water
B. Ice
C. Impure water
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Order of Covalent bond;
A.$$KF > KI; LiF > KF$$
B. $$KF < KI; LiF > KF$$
C. $$SnCl_4 > SnCl_2$$; CuCl > NaCl
D. $$LiF > KF; CuCl > NaCl$$
E. $$KF < KI; CuCl > NaCl$$
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Match Column I with Column II
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Reaction of BeO with ammonia and hydrogen fluoride gives 'A' which on thermal decomposition gives $$BeF_2$$ and $$NH_4F$$. What is 'A' ?
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Increasing order of stability of the resonance structure is:
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Which of the following is true about freons?
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In the depression of freezing point experiment
A. Vapour pressure of the solution is less than that of pure solvent
B. Vapour pressure of the solution is more than that of pure solvent
C. Only solute molecules solidify at the freezing point
D. Only solvent molecules solidify at the freezing point
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Statement I: For colloidal particles, the values of colligative properties are of small order as compared to values shown by true solutions at same concentration.
Statement II: For colloidal particles, the potential difference between the fixed layer and the diffused layer of same charges is called the electrokinetic potential or zeta potential.
In the light of the above statements, choose the correct answer from the options given below.
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Match List I with List II.
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An ammoniacal metal salt solution gives a brilliant red precipitate on addition of dimethylglyoxime. The metal ion is :
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Which of the Phosphorus oxoacid can create silver mirror from $$AgNO_3$$ solution?
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The magnetic moment of a transition metal compound has been calculated to be 3.87 BM. The metal ion is
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The primary and secondary valencies of cobalt respectively in $$Co(NH_3)_5ClCl_2$$ are:
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Assertion A: Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of hydrolysis increases.
Reason R: $$I^-$$ is a good nucleophile as well as a good leaving group.
In the light of the above statements, choose the correct answer from the options given below.
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In the following given reaction 'A' is:
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'A' and 'B' formed in the following set of reactions are:
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'R' formed in the following sequence of reaction is:
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Compound X undergoes following sequence of reactions to give the Lactone Y.
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Given below are two statements :
Statement I : Noradrenaline is a neurotransmitter.
Statement II : Low level of noradrenaline is not the cause of depression in human.
In the light of the above statements, choose the correct answer from the options given below
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If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm, then the wavelength of the second line of this series is _______ nm. (Nearest integer)
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For independent process at 300 K.
The number of non-spontaneous process from the following is _____.
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The dissociation constant of acetic acid is $$x \times 10^{-5}$$. When 25 mL of 0.2 M $$CH_3COONa$$ solution is mixed with 25 mL of 0.02 M $$CH_3COOH$$ solution, the pH of the resultant solution is found to be equal to 5. The value of x is _____.
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Uracil is base present in RNA with the following structure. % of N in uracil is _____.
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When $$Fe_{0.93}O$$ is heated in presence of oxygen, it converts to $$Fe_2O_3$$. The number of correct statement/s from the following is ______.
A. The equivalent weight of $$Fe_{0.93}O$$ is $$\frac{\text{Molecular weight}}{0.79}$$
B. The number of moles of $$Fe^{2+}$$ and $$Fe^{3+}$$ in 1 mole of $$Fe_{0.93}O$$ is 0.79 and 0.14 respectively.
C. $$Fe_{0.93}O$$ is metal deficient with lattice comprising of cubic closed packed arrangement of $$O^{2-}$$ ions.
D. The % composition of $$Fe^{2+}$$ and $$Fe^{3+}$$ in $$Fe_{0.93}O$$ is 85% and 15% respectively.
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5 g of NaOH was dissolved in deionized water to prepare a 450 mL stock solution. What volume (in mL) of this solution would be required to prepare 500 mL of 0.1 M solution? Given : Molar Mass of Na, O and H is 23, 16 and 1 g mol$$^{-1}$$ respectively
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At 298 K, a 1 litre solution containing 10 mmol of $$Cr_2O_7^{2-}$$ and 100 mmol of $$Cr^{3+}$$ shows a pH of 3.0. Given : $$Cr_2O_7^{2-} \to Cr^{3+}$$; $$E^0 = 1.330$$ V and $$\frac{2.303RT}{F} = 0.059$$ V. The potential for the half cell reaction is $$x \times 10^{-3}$$ V. The value of x is _____.
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The number of correct statement/s from the following is _____.
A. Larger the activation energy, smaller is the value of the rate constant.
B. The higher is the activation energy, higher is the value of the temperature coefficient.
C. At lower temperatures, increase in temperature causes more change in the value of k than at higher temperature.
D. A plot of $$\ln k$$ vs $$\frac{1}{T}$$ is a straight line with slope equal to $$-\frac{E_a}{R}$$
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The d-electronic configuration of $$CoCl_4^{2-}$$ in tetrahedral crystal field is $$e^m t_2^n$$. The sum of m and number of unpaired electrons is
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Number of moles of AgCl formed in the following reaction is _____.
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