Practice Questions

Q49.The rate constant for a first order reaction is 20 min−1 . The time required for the initial concentration of the reactant to reduce to its 1 level is ______ × 10−2 min . (Nearest integer) 32

Q49.What happens when a lyophilic sol is added to a lyophobic sol? (1) Film of lyophilic sol is formed over lyophobic (2) Lyophilic sol is dispersed in lyophobic sol sol (3) Film of lyophobic sol is formed over lyophilic (4) Lyophobic sol is coagulated sol

Q49. A →B The above reaction is of zero order. Half life of this reaction is 50 min . The time taken for the concentration of A to reduce to one-fourth of its initial value is min . (Nearest integer)

Q50.Which of the following salt solutions would coagulate the colloid soloution formed when FeCl3 is added to NaOH solution, at the fastest rate? (1) 10 mL of 0. 2 mol dm−3 AlCl3 (2) 10 mL of 0. 1 mol dm−3 Na2 SO4 (3) 10 mL of 0. 1 mol dm−3 Ca3 (PO4)2 (4) 10 mL of 0. 15 mol dm−3 CaCl2

Q50. XeF4 reacts with SbF5 to form [XeFm]n+[SbFy]2− m + n + y + z = ? .

Q50.Match the List-I with List-II : Cations Group reaction P →Pb2+, Cu2+ H2 S gas in presence of dilute HCl Q →Al3+, Fe3+ (NH4)2 CO3 in presence of NH4 OH R →Co2+, Ni2+ NH4 OH in presence of NH4 CI S →Ba2+, Ca2+ H2 S in presence of NH4 OH (1) P →i, Q →iii, R →ii, S →iv (2) P →iv, Q →ii, R →iii, S →i (3) P →iii, Q →i, R →iv, S →ii (4) P →i, Q →iii, R →iv, S →ii

Q50.Match List I and List II List I List II Functional group / Test Class of Compound (A) Molisch's Test (I)Peptide (B) Biuret Test (II)Carbohydrate (C) Carbylamine Test (III) Primary amine (D) Schiff's Test (IV) Aldehyde Choose the correct answer from the options given below: (1) (A) - I, (B) - II, (C) - III, (D) - IV (2) (A) - III, (B) - IV, (C) -I, (D) - II (3) (A) - II, (B) - I, (C) - III, (D) - IV (4) (A) - III, (B) - IV, (C) -II, (D) - I

Q50.In figure, a straight line is given for Freundrich Adsorption (y = 3x + 2. 505). The value of n1 and logK are respectively. JEE Main 2023 (01 Feb Shift 2) JEE Main Previous Year Paper (1) 0. 3 and log 2. 505 (2) 0. 3 and 0. 7033 (3) 3 and 2. 505 (4) 3 and 0. 7033

Q50.The number of colloidal systems from the following, which will have 'liquid' as the dispersion medium, is _____. Gem stones, paints, smoke, cheese, milk, hair cream, insecticide sprays, froth, soap lather

Q50.Given below are two statements: Statement I: During Electrolytic refining, the pure metal is made to act as anode and its impure metallic form is used as cathode. Statement II: During the Hall-Heroult electrolysis process, purified Al2 O3 is mixed with Na3 AlF6 to lower the melting point of the mixture. In the light of the above statements, choose the most appropriate answer from the options given below: (1) Statement I is incorrect but Statement II is (2) Both Statement I and Statement II are incorrect correct (3) Statement I is correct but Statement II is (4) Both Statement I and Statement II are correct incorrect

Q50.The polymer X-consists of linear molecules and is closely packed. It is prepared in the presence of trimethylammoniumpropyl and titanium tetrachloride under low pressure. The polymer X is (1) High density polythene (2) Polyacrylonitrile (3) Low density polythene (4) Polytetrafluoroethane

Q50.Four gases, A, B, C and D have critical temperatures 5. 3, 33. 2, 126. 0 and 154. 3K respectively For their adsorption on a fixed amount of charcoal, the correct order is : (1) C > D > B > A (2) C > B > D > A (3) D > C > B > A (4) D > C > A > B

Q50.Coagulating value of the electrolytes AlCl3 and NaCl tor As2 S3 are 0. 09 and 50. 04 respectively. The coagulating power of AlCl3 is x times the coagulating power of NaCl. The value of x is

Q50.A chloride salt solution acidified with dil. HNO3 gives a curdy white precipitate, [A], on addition of AgNO3 . [A] on treatment with NH4 OH gives a clear solution, B. (1) H[AgCl3]&[Ag (NH3)2] Cl (2) H[AgCl3] & (NH4)[Ag(OH)2] (3) AgCl & [Ag (NH3)2] Cl (4) AgCl & (NH4)[Ag(OH)2]

Q50.Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Ketoses give Seliwanoff’s test faster than Aldoses. Reason (R): Ketoses undergo 𝛽-elimination followed by formation of furfural. In the light of the above statements, choose the correct answer from the options given below: (1) (A) is false but (R) is true (2) Both (A) and (R) are true and (R) is the correct explanation of (A) (3) (A) is true but (R) is false (4) Both (A) and (R) are true but (R) is not the correct explanation of (A)

Q50.Match List I with List II List I List II A Physisorption I Single Layer Adsorption B Chemisorption II 20 −40 kJ mol−1 Fe(s) C III Chromatography− N2(g) + 3H2(g) → 2 NH3(g) D Analytical Application or Adsorption IV Heterogeneous catalysis Choose the correct answer from the options given below: (1) A-III, B-IV, C-I, D-II (2) A-II, B-III, C-I, D-IV (3) A-II, B-I, C-IV, D-III (4) A-IV, B-II, C-III, D-I

Q50.Which one amongst the following are good oxidising agents? (a) Sm2+ (b) Ce2+ (c) Ce4+ (d) Tb4+ Choose the most appropriate answer from the options given below : (1) C only (2) D only (3) A and B only (4) C and D only

Q50.Which one of the following is most likely a mismatch? JEE Main 2023 (13 Apr Shift 1) JEE Main Previous Year Paper (1) Zinc-Liquation (2) Copper-Electrolysis (3) Nickel-Mond process (4) Titanium-van Arkel Method

Q51.Which one of the following statements is incorrect ? (1) van Arkel method is used to purify tungsten. (2) The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace. (3) Cast iron is obtained by melting pig iron with (4) Boron and Indium can be purified by zone scrap iron and coke using hot air blast. refining method.

Q51.The reaction representing the Mond process for metal refining is ______ (1) Δ (2) Δ Ni + 4CO 2K[Au(CN)2] + Zn →K2[Zn(CN)4] + 2 Au →Ni(CO)4 (3) Δ (4) Δ Zr + 2I2 →ZrI4 ZnO + C →Zn + CO Q52.“ A ” obtained by Ostwald's method involving air oxidation of NH3 , upon further air oxidation produces “ B ”. “ B ” on hydration forms an oxoacid of Nitrogen along with evolution of “ A ”. The oxoacid also produces “ A ” and gives positive brown ring test (1) NO2, N2O5 (2) NO2, N2O4 (3) NO, NO2 (4) N2O3, NO2

Q51.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: In the Ellingham diagram, a sharp change in slope of the line is observed from Mg →MgO at ~1120oC Reason R: There is a large change of entropy associated with the change of state In the light of the above statements, choose the correct answer from the options given below (1) Both A and R are true but R is NOT the correct (2) A is false but R is true explanation of A (3) Both A and R are true and R is the correct (4) A is true but R is false explanation of A

Q51. The electron in the nth orbit of Li2 + is excited to ( n + 1 ) orbit using the radiation of energy 1 . 47 × 10-17 J (as shown in the diagram). The value of n is ___________ Given : RH = 2 . 18 × 10-18 J

Q51.The set of correct statements is: (i) Manganese exhibits +7 oxidation state in its oxide. (ii) Ruthenium and Osmium exhibit +8 oxidation in their oxides. (iii) Sc shows +4 oxidation state which is oxidizing in nature. (iv) Cr shows oxidising nature in +6 oxidation state. (1) (ii) and (iii) (2) (i), (ii) and (iv) (3) (i) and (iii) (4) (ii), (iii) and (iv)

Q51.On complete combustion, 0 . 492 g of an organic compound gave 0 . 792 g of CO2. The % of carbon in the organic compound is (Nearest integer)

Q51.The number of bent-shaped molecule/s from the following is ______ N3- , NO2- , I3- , O3, SO2