Practice Questions

Q40.The gas produced by treating an aqueous solution of ammonium chloride with sodium nitrite is (1) NH3 (2) N2 (3) N2O (4) Cl2

Q40.The photochemical smog does not generally contain (1) NO (2) NO2 (3) SO2 (4) HCHO

Q40.Consider the following reaction : (1) Electrolysis 2 HSO−4 (aq) (2) Hydrolysis 2 HSO−4 + 2H+ + A The dihedral angle in product A in its solid phase at 110 K is (1) 104° (2) 111. 5° (3) 90. 2° (4) 111. 0°

Q40.Some gases are responsible for heating of atmosphere (green house effect). Identify from the following the gaseous species which does not cause it. (1) H2O vapour (2) O3 (3) N2 (4) CH4

Q40.Match List I with List II List-I List-II Pollutant Source A Microorganisms I Strip mining B Plant nutrients II Domestic sewage C Toxic heavy metals III Chemical fertilizer D Sediment IV Chemical factory Choose the correct answer from the options given below (1) A - II, B - III, C - IV, D - I (2) A - II, B - I, C - IV, D - III (3) A - I, B - IV, C - II, D - III (4) A - I, B - IV, C - III, D - II

Q40.Two solutions A and B are prepared by dissolving 1 g of non-volatile solutes X and Y. respectively in 1 kg of water. The ratio of depression in freezing points for A and B is found to be 1 : 4. The ratio of molar masses of X and Y is (1) 1 : 4 (2) 1 : 0. 25 (3) 1 : 0. 20 (4) 1 : 5

Q40.In metallurgy the term "gangue" is used for (1) Contamination of undesired earthy materials. (2) Contamination of metals, other than desired metal (3) Minerals which are naturally occuring in pure (4) Magnetic impurities in an ore. form

Q40.Given below are two statements : Statement I: The pentavalent oxide of group- 15 element, E2O5 , is less acidic than trivalent oxide, E2O3 , of the same element. Statement II : The acidic character of trivalent oxide of group 15 elements, E2O3 , decreases down the group. In light of the above statements, choose most appropriate answer from the options given below (1) Both Statement I and Statement II are true. (2) Both Statement I and Statement II are false. (3) Statement I is false but statement II is true. (4) Statement I true, but statement II is false.

Q40.Incorrect statement for Tyndall effect is (1) The refractive indices of the dispersed phase and (2) The diameter of the dispersed particles is much the dispersion medium differ greatly in smaller than the wavelength of the light used. magnitude. (3) It is used to distinguish a true solution from a (4) During projection of movies in the cinemas hall, colloidal solution. Tyndall effect is noticed.

Q40.Sulphur dioxide is one of the components of polluted air. SO2 is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by SO2 is : (1) 2 SO2 + O2 →2 SO3 (2) SO2 + O3 →SO3 + O2 (3) SO2 + H2O2 →H2 SO4 (4) 2 SO2 + O2 + 2H2O →2H2 SO4 Q41. 42. 12% (w/v) solution of NaCl causes precipitation of a certain sol in 10 hours. The coagulating value of NaCl for the sol is [Given : Molar mass : Na = 23. 0 g mol−1; Cl = 35. 5 g mol−1 ] (1) 36 mmolL−1 (2) 36 mol L−1 (3) 1440 mol L−1 (4) 1440 m molL−1

Q41.Concentrated HNO3 reacts with Iodine to give (1) HI, NO2 and H2O (2) HIO2, N2O and H2O (3) HIO3, NO2 and H2O (4) HIO4, N2O and H2O

Q41.Match List - I with List - II. List-I List-II A Concentration of gold ore I Aniline B Leaching of alumina II NaOH C Froth stabiliser III SO2 D Blister copper IV NaCN Choose the correct answer from the options given below. (1) (A) −(IV), (B) −(III), (C) −(II), (D) −(I) (2) (A) −(IV), (B) −(II), (C) −(I), (D) −(III) (3) (A) −(III), (B) −(II), (C) −(I), (D) −(IV) (4) (A) −(II), (B) −(IV), (C) −(III), (D) −(I)

Q41.Boiling point of a 2% aqueous solution of a nonvolatile solute A is equal to the boiling point of 8% aqueous solution of a non-volatile solute B . The relation between molecular weights of A and B is. JEE Main 2022 (27 Jul Shift 1) JEE Main Previous Year Paper (1) MA = 4MB (2) MB = 4MA (3) MA = 8MB (4) MB = 8MA

Q41.The role of depressants in 'Froth Floation method' is to JEE Main 2022 (26 Jun Shift 2) JEE Main Previous Year Paper (1) selectively prevent one component of the ore (2) reduce the consumption of oil for froth from coming to the froth. formation. (3) stabilize the froth. (4) enhance non-wettability of the mineral particles.

Q41.Given below are the oxides : Na2 O, As2 O3, N2O, NO and Cl2 O7 Number of amphoteric oxides is : (1) 0 (2) 1 (3) 2 (4) 3

Q41.In the metallurgical extraction of copper, following reaction is used : FeO + SiO2 →FeSiO3 FeO and FeSiO3 respectively are. (1) gangue and flux. (2) flux and slag (3) slag and flux. (4) Gauge and slag

Q41.Given below are two statements : Statement I : In polluted water values of both dissolved oxygen and BOD are very low. Statement II : Eutrophication results in decrease in the amount of dissolved oxygen. In the light of the above statements, choose the most appropriate answer from the options given below (1) Both Statement I and Statement II are true (2) Both Statement I and Statement II are false (3) Statement I is true but Statement II is false (4) Statement I is false but Statement II is true

Q41.Given below are the critical temperatures of some of the gases: Gas Critical temperature K He 5 . 2 CH4 190 CO2 304 . 2 NH3 405 . 5 The gas showing least adsorption on a definite amount of charcoal is (1) He (2) CH4 (3) CO2 (4) NH3

Q41.In neutral or alkaline solution, MnO−4 oxidises thiosulphate to (1) S2O2−7 (2) S2O2−8 (3) SO2−3 (4) SO2−4

Q41.Which of the following is a correct statement? (1) Brownian motion destabilises sols. (2) Any amount of dispersed phase can be added to emulsion without destabilising it. (3) Mixing two oppositely charged sols in equal (4) Presence of equal and similar charges on amount neutralises charges and stabilises colloidal particles provides stability to the colloids. colloidal solution.

Q41.Given below are two statements: one is labelled as Assertion and the other is labelled as Reason. Assertion: Flourine forms one oxoacid. Reason: Flourine has smallest size amongst all halogens and is highly electronegative. In the light of the above statements, choose the most appropriate answer from the Question: options given below. (1) Both assertion and reason are correct and reason is the correct explanation of assertion. (2) Both assertion and reason are correct and but reason is not the correct explanation of assertion. (3) Assertion is correct and reason is incorrect (4) Assertion is incorrect and reason is correct

Q41.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. (1) Both Statement I and Statement II are true. (2) Both Statement I and Statement II are false. (3) Statement I is true but Statement II is false. (4) Statement I is false but Statement II is true.

Q41.The molar conductivity of a conductivity cell filled with 10 moles of 20 mL NaCl solution is Λm1 and that of 20 moles another identical cell heaving 80 mL NaCl solution is Λm2 , The conductivities exhibited by these two cells are same. The relationship between Λm2 and Λm1 is (1) Λm2 = 2Λm1 (2) Λm2 = Λm1/2 (3) Λm2 = Λm1 (4) Λm2 = 4Λm1

Q41.At 30 °C, the half life for the decomposition of AB2 is 200 s and is independent of the initial concentration of AB2. The time required for 80% of the AB2 to decompose is (Given: log2 = 0 . 30; log3 = 0 . 48) (1) 200s (2) 323s (3) 467s (4) 532s

Q41.The correct order of melting points of hydrides of group 16 elements is (1) H2S < H2Se < H2Te < H2O (2) H2O < H2S < H2Se < H2 Te (3) H2S < H2Te < H2Se < H2O (4) H2Se < H2S < H2Te < H2O