Practice Questions

Q44.An aqueous solution of a salt MX2 at certain temperature has a Van't Hoff factor of 2 . What is the degree of dissociation for this solution of the salt? (1) 0. 50 (2) 0. 33 (3) 0. 67 (4) 0. 80

Q44.BOD stands for: (1) Bacterial Oxidation Demand (2) Biological oxygen demand (3) Biochemical oxygen demand (4) Both A and B

Q45.Oxidation of succinate ion produces ethylene and carbon dioxide gases. On passing 0. 2 Faraday electricity through an aqueous solution of potassium succinate, what is the total volume of gases (at both cathode and anode) at STP ( 1 atm and 273 K)? (1) 8. 96 L (2) 4. 48 L (3) 6. 72 L (4) 2. 24 L

Q45.Galvanization is applying a coating of: (1) Cu (2) Zn (3) Pb (4) Cr

Q45.The solubility of N2 in water at 300 K and 500 torr partial pressure is 0 .01 g L−1. The solubility (in g L−1 ) at 750 torr partial pressure is: (1) 0.0075 (2) 0.005 (3) 0. 02 (4) 0.015

Q46.What will happen when a block of copper metal is dropped into a beaker containing a solution of 1 M ZnSO4 ? (1) The copper metal will dissolve with evolution of (2) The copper metal will dissolve with evolution of oxygen gas. hydrogen gas. (3) No reaction will occur. (4) The copper metal will dissolve and zinc metal will be deposited.

Q46.Identify the correct statement: JEE Main 2016 (10 Apr Online) JEE Main Previous Year Paper (1) Corrosion of iron can be minimised by forming a (2) Iron corrodes in oxygen-free water contact with another metal with a higher reduction potential (3) Corrosion of iron can be minimised by forming (4) Iron corrodes more rapidly in salt water because an impermeable barrier at its surface its electrochemical potential is higher

Q46.Decomposition of H2O2 follows a first order reaction. In fifty minutes the concentration of H2O2 decreases from 0.5 to 0.125 M in one such decomposition. When the concentration of H2O2 reaches 0.05 M , the rate of formation of O2 will be: JEE Main 2016 (03 Apr) JEE Main Previous Year Paper (1) 2.66 Lmin−1 at STP (2) 1.34 × 10−2 mol min−1 (3) 6.93 × 10−2 mol min−1 (4) 6.93 × 10−4 mol min−1

Q47.The reaction of ozone with oxygen atoms in the presence of chlorine atoms can occur by a two step process shown below: O3(g) + Cl∙→O2(g) + ClO∙(g) ...(i) ki = 5.2 × 109 L mol−1 s−1 ClO∙(g) + O∙(g) →O2(g) + Cl∙(g) ...(ii) kii = 2.6 × 1010 L mol−1 s−1 JEE Main 2016 (09 Apr Online) JEE Main Previous Year Paper The closest rate constant for the overall reaction O3(g) + O∙(g) →2O2(g) is: (1) 1.4 × 1020 L mol−1 s−1 (2) 3.1 × 1010 L mol−1 s−1 (3) 5.2 × 109 L mol−1 s−1 (4) 2.6 × 1010 L mol−1 s−1

Q47.For a linear plot of log ( mx ) versus log p in a Freundlich adsorption isotherm, which of the following statements is correct? ( k and n are constants) (1) Only n 1 appears as the slope. (2) log( n1 ) appears as the intercept. (3) Both k and n1 appear in the slope term. (4) n1 appears as the intercept.

Q47.The rate law for the reaction below is given by the expression k[A][B] A + B →Product If the concentration of B is increased from 0. 1 to 0. 3 mol , keeping the value of A at 0. 1 mol , the rate constant will be: (1) 3k (2) 9k (3) k/3 (4) k

Q48.The hottest region of Bunsen flame shown in the figure below is: (1) Region 3 (2) Region 4 (3) Region 1 (4) Region 2

Q48.Gold numbers of some colloids are Gelatin: 0. 005 −0. 01, Gum Arabic: 0. 15 −0. 25, Oleate: 0. 04 −1. 0 , Starch: 15 −25 . Which among the following is a better protective colloid? (1) Gelatin (2) Starch (3) Oleate (4) Gum Arabic

Q48.A particular adsorption process has the following characteristics: (i) It arises due to van der Waals forces and (ii) it is reversible. Identify the correct statement that describes the above adsorption process: (1) Adsorption is monolayer (2) Adsorption increases with increase in temperature (3) Enthalpy of adsorption is greater than (4) Energy of activation is low 100 kJ mol−1

Q49.The most appropriate method of making egg-albumin sol is: (1) Break an egg carefully and transfer the (2) Keep the egg in boiling water for 10 minutes. transparent part of the content to 100 mL of 5% After removing the shell, transfer the yellow part w/V saline solution and stir well of the content to 100 mL of 5% w/V saline solution and homogenize with a mechanical shaker (3) Keep the egg in boiling water for 10 minutes. (4) Break an egg carefully and transfer only the After removing the shell, transfer the white part yellow part of the content to 100 mL of 5% w/V of the content to 100 mL of 5% w/V saline saline solution and stir well solution and homogenize with a mechanical shaker

Q49.Which one of the following ores is best concentrated by froth flotation method? (1) Galena (2) Malachite (3) Magnetite (4) Siderite

Q49.Extraction of copper by smelting uses silica as an additive to remove. (1) Cu2O (2) FeS (3) FeO (4) Cu2S

Q50.Identify the incorrect statement : (1) The S-S-S bond angles in the S8 and S6 rings are (2) Rhombic and monoclinic Sulphur have S8 the same. molecules. (3) S2 is paramagnetic like oxygen. (4) S8 ring has a crown shape.

Q50.The pair in which phosphorous atoms have a formal oxidation state of + 3 is: (1) Orthophosphorous and hypophospheric acids (2) Pyrophosphorous and pyrophosphoric acids (3) Orthophosphorous and pyrophosphorous acids (4) Pyrophosphorous and hypophosphoric acids

Q50.The plot shows the variation of −ln KP Versus temperature for the two reactions. M(s) + 12 O2(g) →MO(s) and C(s) + 12 O2(g) →CO(s) Identify the correct statement: (1) At T < 1200 K, oxidation of carbon is (2) Oxidation of carbon is favourable at all unfavourable temperatures (3) At T < 1200 K, the reaction (4) At T > 1200 K, carbon will reduce MO(s) + C(s) →M(s) + CO(g) is spontaneous MO(s) to M(s) .

Q51.The non-metal that does not exhibit positive oxidation state is: (1) Chlorine (2) Iodine (3) Fluorine (4) Oxygen JEE Main 2016 (09 Apr Online) JEE Main Previous Year Paper

Q51.The reaction of zinc with dilute and concentrated nitric acid, respectively, produces: (1) NO and N2O (2) NO2 and N2O (3) N2O and NO2 (4) NO2 and NO

Q51.Which of the following are the transition metal ions responsible for colour in ruby and emerald respectively? (1) Co3+ and Cr3+ (2) Co3+ and Co3+ (3) Cr3+ and Cr3+ (4) Cr3+ and Ag+

Q52.Which one of the following species is stable in aqueous solution? (1) Cr2+ (2) MnO2−4 (3) MnO3−4 (4) Cu+

Q52.Find the metallic and ferromagnetic substance. (1) VO2 (2) MnO2 (3) TiO2 (4) CrO2