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What is the work function of the metal if the light of wavelength 4000 $$\mathring{A}$$ generates photoelectrons of velocity $$6 \times 10^5$$ ms$$^{-1}$$ from it? (Mass of electron $$= 9 \times 10^{-31}$$ kg, velocity of light $$= 3 \times 10^8$$ ms$$^{-1}$$, Planck's constant $$= 6.626 \times 10^{-34}$$ Js, Charge of electron $$= 6.626 \times 10^{-34}$$ Js)
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The element with Z = 120 (not yet discovered) will be a/an
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Given
On the basis of data given above, predict which of the following gases shows the least adsorption on a definite amount of charcoal?
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The volume of gas A is twice than that of gas B. The compressibility factor of gas A is thrice than that of gas B at same temperature. What are the pressures of the gases for equal number of moles?
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For a diatomic ideal gas in a closed system, which of the following plots does not correctly describe the relation between various thermodynamic quantities?
In a chemical reaction, $$A + 2B \xrightleftharpoons{K} 2C + D$$, the initial concentration of B was 1.5 times the concentration of A, but the equilibrium concentrations of A and B were found to be equal. The equilibrium constant (K) for the chemical reaction is:
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Two solids dissociate as follows: $$A(s) \rightleftharpoons B(g) + C(g)$$; $$K_{P_1} = x$$ atm$$^2$$, $$D(s) \rightleftharpoons C(g) + E(g)$$; $$K_{P_2} = y$$ atm$$^2$$. The total pressure when both the solids dissociate simultaneously is:
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50 mL of 0.5 M oxalic acid is needed to neutralize 25 mL of sodium hydroxide solution. What is the amount of NaOH in 50 mL of the given sodium hydroxide solution?
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What is the hardness of a water sample (in terms of equivalents of CaCO$$_3$$) containing $$10^{-3}$$ M CaSO$$_4$$? (Molar mass of CaSO$$_4$$ = 136 g mol$$^{-1}$$)
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A metal on combustion in excess air forms X. X upon hydrolysis with water yields $$H_2O_2$$ and $$O_2$$ along with another product. The metal is:
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Among the following four aromatic compounds, which one will have the lowest melting point?
The correct order for acid strength of compounds $$CH \equiv CH$$, $$CH_3 - C \equiv CH$$ and $$CH_2 = CH_2$$ is as follows:
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The major product of the following reaction is:
Water samples with BOD values of 4 ppm and 18 ppm, respectively, are:
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The molecule that has minimum or no role in the formation of photochemical smog, is:
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The freezing point of a 4% aqueous solution of X is equal to the freezing point of a 12% aqueous solution of Y. If the molecular weight of X is A, then the molecular weight of Y will be
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The standard electrode potential E° and its temperature coefficient $$\left(\frac{dE}{dT}\right)$$ for a cell are 2 V and $$-5 \times 10^{-4}$$ V K$$^{-1}$$ at 300 K, respectively. The reaction is Zn(s) + Cu$$^{2+}$$(aq) $$\to$$ Zn$$^{2+}$$(aq) + Cu(s). The standard reaction enthalpy $$(\Delta_r H^-)$$ at 300 K in mol$$^{-1}$$ is [Use R = 8 J K$$^{-1}$$ mol$$^{-1}$$ and F = 96,500 C mol$$^{-1}$$]
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Decomposition of X exhibits a rate constant of 0.05 $$\mu$$g/year. How many years are required for the decomposition of 5 $$\mu$$g of X into 2.5 $$\mu$$g?
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In the Hall-Heroult process, aluminium is formed at the cathode. The cathode is made out of:
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Iodine reacts with concentrated $$HNO_3$$ to yield Y along with other products. The oxidation state of iodine in Y, is:
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The pair of metal ions that can give a spin only magnetic moment of 3.9 BM for the complex $$[M(H_2O)_6]Cl_2$$, is:
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The metal's d-orbitals that are directly facing the ligands in $$K_3[Co(CN)_6]$$ are:
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$$Mn_2(CO)_{10}$$ is an organometallic compound due to the presence of:
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cannot be prepared by:
In the following reactions, products A and B are:
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The major product of the following reaction is:
In the following reaction:
The best combination is:
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The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is:
Poly-$$\beta$$-hydroxybutyrate-co-$$\beta$$-hydroxyvalerate (PHBV) is a copolymer of ____.
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Among the following compounds most basic amino acid is:
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