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The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is:
[Given: The threshold frequency of platinum is $$1.3 \times 10^{15}$$ s$$^{-1}$$ and $$h = 6.6 \times 10^{-34}$$ Js]
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What is the correct order of electron gain enthalpy of Cl, F, Te, Po
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At $$25°$$C and $$1$$ atm pressure, the enthalpy of combustion of benzene $$1$$ and acetylene $$g$$ are $$-3268$$ kJ mol$$^{-1}$$ and $$-1300$$ kJ mol$$^{-1}$$, respectively. The change in enthalpy for the reaction
$$3C_2H_2(g) \to C_6H_6(l)$$, is
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The $$K_{sp}$$ for bismuth sulphide $$Bi_2S_3$$ is $$1.08 \times 10^{-73}$$. The solubility of $$Bi_2S_3$$ in mol L$$^{-1}$$ at $$298$$ K is
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Assertion: The amphoteric behaviour of water is explained by Lewis acid base theory
Reason: water acts as acid with $$NH_3$$ and base with $$H_2S$$
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The number of bridged oxygen atoms present in compound B formed from the following reactions is
$$PbNO_{3_2} \xrightarrow{673 K} A + PbO + O_2$$
$$A \xrightarrow{Dimerise} B$$
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Given below are two statements: one is labelled as Assertion and the other is labelled as Reason.
Assertion: A mixture contains benzoic acid and naphthalene. The pure benzoic acid can be separated out by the use of benzene.
Reason: Benzoic acid is soluble in hot water.
In the light of the above statements, choose the most appropriate answer from the options given below.
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Given below are two statements: one is labelled as Assertion and the other is labelled as Reason.
Assertion: Polluted water may have a value of BOD of the order of 17ppm.
Reason: BOD is a measure of oxygen required to oxidise both the biodegradable and non-biodegradable organic material in water.
In the light of the above statements, choose the most appropriate answer from the options given below.
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Solute A associates in water. When $$0.7$$ g of solute A is dissolved in $$42.0$$ g of water, it depresses the freezing point by $$0.2°$$C. The percentage association of solute A in water, is
[Given: Molar mass of A $$= 93$$ g mol$$^{-1}$$. Molal depression constant of water is $$1.86$$ K kg mol$$^{-1}$$]
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The correct order of reduction potentials of the following pairs is
A. $$Cl_2/Cl^-$$
B. $$I_2/I^-$$
C. $$Ag^+/Ag$$
D. $$Na^+/Na$$
E. $$Li^+/Li$$
Choose the correct answer from the options given below.
Given below are two statements.
Statement I: During electrolytic refining, blister copper deposits precious metals.
Statement II: In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.
In the light of the above statements, choose the correct answer from the options given below.
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The metal ion (in gaseous state) with lowest spin-only magnetic moment value is
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In the given reaction
'A' can be
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Amongst the following, the major product of the given chemical reaction is
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The major product formed in the following reaction, is
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Which of the following conditions or reaction sequence will NOT give acetophenone as the major product?
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During halogen test, sodium fusion extract is boiled with concentrated $$HNO_3$$ to
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Which of the following ketone will NOT give enamine on treatment with secondary amines? [where t-Bu is $$-C(CH_3)_3$$]
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Match the following correctly
(i) Zymase - (a) Stomach
(ii) Urease - (b) Yeast
(iii) Diastase - (c) Malt
(iv) Pepsin - (d) Soyabean
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An antiseptic dettol is a mixture of two compounds 'A' and 'B' where A has $$6\pi$$ electrons and B has $$2\pi$$ electrons. What is B?
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A protein 'A' contains $$0.30\%$$ of glycine (molecular weight $$75$$). The minimum molar mass of the protein 'A' is ______ $$\times 10^3$$ g mol$$^{-1}$$ [nearest integer]
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How many of the following molecules are with non-zero net dipole moment,
$$NH_3$$, HCl, $$H_2O$$, $$BeF_2$$, $$BH_3$$, $$CCl_4$$
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A rigid nitrogen tank stored inside a laboratory has a pressure of $$30$$ atm at $$06:00$$ am when the temperature is $$27°$$C. At $$03:00$$ pm, when the temperature is $$45°$$C, the pressure in the tank will be ______ atm. [nearest integer]
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The neutralization occurs when $$10$$ mL of $$0.1$$ M acid 'A' is allowed to react with $$30$$ mL of $$0.05$$ M base $$MOH_2$$. The basicity of the acid 'A' is ______
[M is a metal]
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A solution of $$Fe_2(SO_4)_3$$ is electrolyzed for '$$x$$' min with a current of $$1.5$$ A to deposit $$0.3482$$ g of Fe. The value of $$x$$ is ______ [nearest integer]
Given : $$1 F = 96500$$ C mol$$^{-1}$$. Atomic mass of Fe $$= 56$$ g mol$$^{-1}$$
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At $$345$$ K, the half life for the decomposition of a sample of a gaseous compound initially at $$55.5$$ kPa was $$340$$ s. When the pressure was $$27.8$$ kPa, the half life was found to be $$170$$ s. The order of the reaction is ______ [integer answer]
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$$PCl_5 + H_2O \to A + HCl$$
$$A + H_2O \to B + HCl$$
Find number of ionisable hydrogen in B
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Amongst $$FeCl_3 \cdot 3H_2O$$, $$K_3[Fe(CN)_6]$$ and $$[Co(NH_3)_6]Cl_3$$, the spin-only magnetic moment value of the inner-orbital complex that absorbs light at shortest wavelength is ______ B.M. [nearest integer]
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The Novolac polymer has mass of $$963$$ g. The number of monomer units present in it are ______
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How many of the given compounds will give a positive Biuret test? ______
Glycine, Glycylalanine, Tripeptide, Biuret
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