General Questions and Answers

38 What volume of 0 20 M H SO4 is required to produce 34 0g of H S by the reaction 8KI 5H SO4 4K2SO4 412 H S 4H O

1 HNO acts as an oxidant with which one of the following reagent 1 KMnO 2 H S 3 K Cr O 4 Br

The percentage of sodium in a breakfast cereal labelled as 110 mg of sodium per 100 g of cereal is a 11 b 01 10 d 110 c 0 110

2 40 At what pH does an indicator change colour if the indicator is a weak acid with K 4x 10 F which one s of the following neutralizations would the indicator be useful Explain ind a NaOH CH COOH b HCI NH c HCl NaOH What indicator should be used for the titration of 10MKH BO with 1MUCH 0 41

n factor of HCI in the reaction KMnO HCI KCI MnCl Cl H O 4 1 1 2 6 3 5 8 4 00 L

Polychlorinated biphenyls PCBs known to be dangerous environmental pollutants are a group of compounds with the general empirical formula C HC10 m where m is an integer What is the value of m and hence the empirical formula of the PCB that contains 58 9 chlorine by mass

In the reaction VO Fe O3 FeO V 05 the eq wt of V O is equal to its OAM 1 Mol wt 2 Mol wt 8 3 Mol wt 6 4 None of these

Redox reactions play a pivotal role in chemistry and biology The values of standard redox potential E of two half cell reactions decide which way the reaction is expected to proceed A simple example is a Daniel cell in which zinc goes into solution and copper gets deposited For the cell Pt H 0 4 atm H pH 1 H pH 2 H 0 1 atm Pt The measured potential at 25 C is Given 2 303 RT F 0 06V log 2 0 3 A 0 1 V B 0 5 C 0 042 D 0 035

0 A gaseous alkane was exploded with oxygen The volume of O for complete combustion to CO formed was in the ratio of 7 4 The molecular formula of alkane is 2 a CH4 c C3H6 b C H6 d C4H10

Which of the following is true about the charge acquired by p type semiconductor A B C D Positive Neutral Negative Depends on concentration of p impurity

The graphs representing distribution of molecular speeds at 300 K for gases Cl and N are as shown in figure atomic mass N 14 Cl 35 5 fraction of molecules I II x molecular speed a I graph is for N and II is for Cl b II graph is for N and I is for Cl c either graph can be taken for N or Cl d information is not sufficient

ml of 0 1 M KC1 200 ml of 0 01 M NaNO3 and 500 mL of 0 1 M AgNO was mixed The molarity of K Ag C NO3 in the solution would be K 0 04 Ag 0 04 Na 0 002 CI 0 04 NO3 0 042 K 0 04 Na 0 002 NO3 0 0433 K 0 04 Ag 0 05 Na 0 0025 CI 0 05 NO3 0 0525 K1 0 05 INa 1 0 0025 NO 0 0525

4 Physical adsorption is inversely proportional to a Volume b Concentration c Temperature A

50 For the following processes AH KJ Mol A B 2B C D y E B 3 C Z For 2A 3B 3D E AH will be 1 2z x 2y 3 z 2x 2y X 2 z 2x 3y 4 2 2x 3x

photon of wavelength 4x10 m strikes on metal surface the work function of the metal being 2 13 eV Calculate the energy of the photon eV i the kinetic energy of the emission and ii the velocity of the photoelectron GV 16020x10 29

9 0 1 g atom of radioactive isotope zXA half life 5 day is taken How many number of atoms will decay Roorkee 1988 during eleventh day DI 206

The highest electrical conducitivity of the following aqueous solution is of 1 0 1 M fluoroacetic acid 2 0 1 M difluoroacetic acid 4 0 1 M chloroacetic acid 3 0 1 M acetic acid

The solubility of K SO4 in water is 16 g at 50 C The minimum amount of water required to dissolve 4 g K SO4 is a 10 g b 25 g c 50 g d 75 g

9 64 Cu half life 12 8 h decays by emission 38 emission 19 and electron capture 43 Write the decay products and calculate partial half lives for each of the decay processes IIT 2002

The mass of a non volatile solute of molar mass 40 g mol that should be dissolved in 114 g of octane to lower its vapour pressure by 20 is a 10 g c 9 8 g b 11 4 g d 12 8 g 2012

asks are separately filled with the gases CO2 F2 NH3 and He at same room temperature and pressure The ratio of total number of atoms of these gases present in the different flasks would be 1 1 1 1 1 2 1 2 2 3 3 3 2 4 1

Arrange the following in order of a Increasing oxidation no MnCl2 MnO2 Mn OH 3 KMnO 4 b Decreasing oxidation no HXO4 HXO3 HXO2 HXO c Increasing oxidation no 1 HI HIO 4 ICl

Uncertainty in position of a minute particle of m 25 g in space is 10 5m The uncertainty in its velo in ms is AIEEE 200 a 2 1x 10 34 c 2 1x 10 28 b 0 5x 10 34 d 0 5 x 10 23

How many metals are commercially reduced by Gold schmidt alumino thermite process from the given metals Na Pb Al Mn Cr Sn

If the percent yield for the following reaction is 65 0 how many grams of KCIO are needed to produce 42 0 g of O 2KCIO3 s 2KCl s 30 g B 107 g A 69 7 g C 165 g D 371 g

Of the following which of the statement s regarding Bohr theory is wrong n IS a Kinetic energy of an electron is half of the magnitude of its potential energy a b Kinetic energy of an electron is negative of total 90x1 2 energy of electron c Energy of electron decreases with increase in the value of the principal quantum number d The ionization energy of H atom in the first excited state is negative of one fourth of the energy of an electron in the ground state

4 The ratio of masses of oxygen and nitrogen in particular gaseous mixture is 1 4 The ratio o number of their molecule is JEE Mains 2014 a 1 4 b 7 32 d 3 16

21 Consider the following reaction 2 Z xMnO4 yC 02 zH xMn 2yCO H 2 The values of x y and z in the reaction JEE Mains 201 respectively a 2 5 and 8 c 5 2 and 8 b 2 5 and 16 d 5 2 and 16

11 In what pH range will a 1 x 10 4 M solution of an indicator will K indicator 1 x 10 change colour A 7 0 1 B 3 0 1 C 5 5 1 D 11 0 1 K 10x10 5 The acid form of the indicator is red and the basic She

A chemical compound dioxin has been very much in the news in the past few years It is the by produc of herbicide manufacture and is thought to be quite toxic Its formula is C 2H4Cl O2 If you have a sample dirt 28 3 g that contains 8 78 x 10 8 moles of dioxin calculate the percentage of dioxin in the dirt sample ant Academy 1 Pvt Ltd B 41 Road No 2 IPIA Kota Raj Ph 06377791915 www vibrantacademy com 15

What is the value of n in the following equation Cr OH OH CrO2 H O ne 4 1 3 3 5 2 6 4 2

For combustion of 1 mole of benzene at 25 C the heat of reaction at constant pressure is 780 9 kcal What will be the heat of reaction at constant volume CH6 1 72 02 g 6CO2 g 3H O 1 a 781 8 kcal c 781 8 kcal b 780 0 kcal d 780 0 kcal

What weight of 75 0 NaOH by weight must be dissolved in water to prepare 250 mL of 1 50 M NaOH FW 40 0 A 20 0 g C 11 2 g D 5 33 g B 15 0 g SECTION MATRIY

A metal M of atomic mass 54 94 has a density of 7 42g cm Calculate the volume occupied and the radius of the atom of this metal assuming it to be a sphere

12 The oxide which cannot act as a reducing agent is a CO c NO b ClO d SO 1995 13 Which substance is serving as a reducing agent in the following reaction 14H Cr 0 3Ni 7H O 3Ni a H b CrO d Ni c H O 1994 14 The oxidation state of I in H4106 is b 1 d 5 15 a 1 c 7 1994 On electrolysis of dilute sulphuric acid using platinum electrodes the product obtained at the anode will be a hydrogen b oxygen c hydrogen sulphide d sulphur dioxide 1992

22 The molarity of a solution obtained by mixing 750 mL of 0 5 M HCl with 250 mL of 2 M HCl will be a 1 00 M c 0 975 M JEE Mains 2013 b 1 75 M d 0 875 M

A compound was found to contain 14 34 oxygen The minimum molecular weight of the compound is 1 111 5 g 2 223 15 g 3 97 62 g A 495 26 a

CsBr crystallises in a body centred cubic lattice The unit cell length is 436 6 pm Given that the atomic mass of Cs 133 and that of Br 80 amu and Avogadro number being 6 023 x 1023 mol 1 the density of CsBr is 1 42 5 g cm 3 8 25 g cm 3 2 0 425 g cm 4 4 25 g cm

Problem 9 3 Can phosphorus with outer electroni configuration 3s 3p form PH

Write the balanced chemical equation for the following and identify the type of reaction in each case Potassium iodide aq Barium bromide s a Potassium bromide aq Barium iodide aq b Zinc carbonate s Zinc oxide s Carbon dioxide g c Hydrogen g Chlorine g Hydrogen chloride g d Magnesium s Hydrochloric acid aq Magnesium chloride aq Hydrogen

5 A 0 66 kg ball is moving with a speed of 100 m s The associated wavelength will be h 6 6 x 10 4 Js 34 1 6 6 10 34 X m 3 1 0 x 10 32 m 2 1 0 10 35 m 4 6 6 x 10 32 m

5 What mass of C 4 with t1 2 equal to one curie 5730 year has activit Roorkee 1986

0 A metal surface of threshold frequency 5 3 10 4 sec 1 is exposed to a photon of radiation having energy 3 5x10 19 J Will it exhibit photoelectric effect

Iron exhibits bcc structure at room temp Above 900 C it transforms to fcc structure The ratio of density of iron at room temperature to that at 900 C assuming molar mass and atomic radij of iron remains constant with temperature is 3 2 1 2 4 3 3 2 3 291625 3 3 4 2 4 13 2

11 2 g carbon reacts completely with 19 63 litre of 0 2 at NTP The cooled gases are passed through 2 litre of 2 5N NaOH solution Calculate concentration of remaining NaOH and Na CO3 in solution CO does not react with NaOH under these conditions

1 A non volatile solute A tetramerises in water to the extent of 80 2 5 g of A in 100 g of water lowers the freezing point by 0 3 C The molar mass of A in mol L is K for water 1 86 K kg mol a 62 c 155 b 221 d 354 2019

Based on the hints given find out the atomic number and write down the subshell electronic configuration of elements Symbols used are not real i A period 3 group 17 ii B period 4 group 6 When the last electron of an atom was filled in the 3d subshell the subshell electronic configuration was 3d Answer the questions related to this atom Complete subshell electronic configuration Atomic number Block umber

The dipole moment of The dipole moment of B 1 D 1 5 D Correct Answer C 2 25 D Your Answer X is 1 5 D is

4 Which mode of expressing concentration is independent of temperature a Molarity c Formality mn1 b Molality d Normality

27 790 28 53 The substance having highest conductivity at room temperature among the following is a 0 1 N HC1 c graphite PO b d 0 1 N NaCl 2015 TAST glass TISTIUS mivo offs ai re