One mole of an anhydrous salt AB dissolves in water with the evolution of 21.0 J/mol of heat. If the heat of hydration of AB is -29.4 J/mol then the heat of dissociation of the hydrated salt AB is 1) 50.4 J/mol 2) 8.4 J/mol 3) -54.4 J/mol 4) -8.4 J/mol
0.56 g of limestone was treated with oxalic acid to give CaC2?O4?. The precipitate decolorised 45 mL of 0.2 N KMnO4? in acid solution. Calculate the % of CaO in limestone.
1) 15
2) 20
3) 34
4) 45
0.1 M solution of KI reacts with excess of $$H_2SO_4$$ and $$KIO_3$$ solutions according to equation: $$5I^{-}+IO_3^-+6H\rightarrow 3I_2+3H_2O$$ Which of the following statement is correct? 1) $$200$$ ml of the $$KI$$ solution reacts with $$0.004$$ mol $$KIO_3$$. 2) $$100$$ ml of the $$KI$$ solution reacts with $$0.006$$ mol of $$H_2SO_4$$. 3) $$0.5$$ litres of the $$KI$$ solution produced $$0.005$$ mol of $$I_2$$ 4) Equivalent weight of $$KIO_3$$ is equal to $$(\dfrac{Molecular\: weight}{5})$$.
H2 gas was adsorbed on 1 g powdered copper surface forming monolayer of molecules. On desorption, total H2 collected measured 1.36cm2 at STP. Assuming the volume of 1 molecule of H2? to be 4.472×10−23cm3, the specific area of copper powder turns out to be y×102cm2. Find the value of y.
1) 579 2) 456 3) 57.9 4) 45.6
The rate constant for a second order reaction is 8×10−5M−1 min−1. How long will it take a 1M solution to be reduced to 0.5M?
1) 8.66 × 103 minute 2) 8×10−5 minute 3) 1.25×104 minute 4) 4×10−5 minute
The compressibility factor of gas is more than unity at STP. Its value of Vm is 1) Equal to 22.4 dm3 2) Dependent on its molecular size 3) Greater than 22.4 dm3 4) lesser than 22.4dm3
When sodium hydroxide solution is added to a freshly prepared solution of ferrous sulphate, a green precipitate of ferrous hydroxide is formed which on standing turns brown because:
1) ferric salts are unstable 2) the mixture becomes dirty 3) ferrous hydroxide becomes ferric oxide 4) green ferrous hydroxide oxidises to brown ferric hydroxide
The function of automobile catalytic converter is to control emissions of:
1) carbon dioxide and hydrogen
2) carbon monoxide and hydrogen
3) carbon monoxide and carbon dioxide
4) carbon monoxide and nitrogen dioxide
On the basis of Le Chatellier principle, predict which of the following conditions would be unfavorable for the formation of SO3? Given that 2SO2 + O2 ↔ 2SO3 ; ΔH=-42 kcal 1) Low pressure 2) High pressure 3)high temperature 4)high concentration of SO2
The techniques of gas liquid chromatography is suitable for compounds which are?
1) Soluble in water
2) Highly volatile
3) Vaporise without decompostion
4) Liquids
600 m of a mixture of O3 and O2 weight 1 g at NTP. Calculate the volume of ozone in the mixture.
1) 400 ml 2) 600 ml 3) 200 ml 4) 100 ml
At a particular temperature, the vapour pressures of two liquids A and B are respectively 120 and 180 mm of mercury. If 2 moles of A and 3 moles of B are mixed to form an ideal solution, the vapour pressure of the solution at the same temperature will be ( in mm of mercury)
1) 156 2) 145 3) 150 4) 48
Equal masses of ethane and hydrogen are mixed in an empty container at 25°C. The fraction of total pressure exerted by hydrogen is 1) 1 : 2 2) 1 : 1 3) 1 : 16 4) 15 : 16
For a certain crystal system the relation between edge lengths (a, b, and c) is a = b = c The relation between axial angles (α,βandγ)(α,βandγ) is α=β=γ . The pair of crystal system for which above relation holds true is: 1) cubic and triclinic 2) cubic and tetragonal 3) hexagonal and orthorhombic 4) cubic and rhombohedral???????
0.2 g of an organic compound gave 0.17 g NH3? in kjeldhal's method. The percentage weight of nitrogen in the given compound is:
1) 70% 2) 80% 3) 50% 4) 90%
The compound $$A$$ on heating gives a colourless gas and a residue that is dissolved in water to obtain $$B$$. Excess of $$CO_2$$ is bubbled through an aqueous solution of $$B, C$$ is formed which is recovered in the solid form. Solid $$C$$ on gentle heating gives back $$A$$. The compound $$A$$ is:
1) $$CaCO_3$$ 2) $$Na_2CO_3$$ 3) $$K_2CO_3$$ 4) $$CaSO_4.2H_2$$O
An element having bcc geometry has atomic mass 50. Calculate the density of the unit cell, if its edge length is 290 pm 1) 68.1g/cm3 2) 5.81g/cm3 3) 6.81g/cm3 4) none
If 1mL of a KMnO4 solution react with 0.140 g Fe2+ .140 g Fe2+ and if 1mL1mL of KHC2O4. H2C2O4 solution react with 0.1mL of previous KMnO4 solution, how many millilitres of 0.20M NaOH will react with 1mL of previous KHC2O4. H2C2O4 solution in which all the protons (H+) are ionisable?
1) 15 / 16mL 2) 13/ 16 3) 11 / 14 4) None
The pH of a 10ml aqueous solution of HCl is 4 The amount of water to be added to this solution in order to change its pH from 4 to 5 is?
1) 30 ml 2) 60 ml 3) 90 ml 4) 120ml
A substance X is a compound of an element of group IA. The substance X gives a violet colour in flame test. X is
1) NaCl
2) KCl
3) LiCl
4) None
In which of the following compounds transition metal has zero oxidation state?
1) CrO5 2) NH2⋅NH2 3) NOClO4 4) [Fe(CO)5]
The element which, forms oxides in all oxidation states varying from +1 to +5 is: 1) N 2) P 3) As 4) Sb
The final step for the extraction of copper from copper pyrites in Bessemer converter the reaction involves is as : 1) Cu2S + 2FeO ?2Cu + 2Fe + SO2 2) Cu2S + 2CuO ? 6Cu + SO2 3) 4Cu2S + FeS? 8Cu + 2FeSO4 4) 2Cu2O+FeS?4Cu+2Fe+SO2
Which of the following statements are correct about dissociation?
1) Dissociation generally refers to breaking a compound into smaller pieces, usually reversibly. 2) Dissociation can happen without the formation of charged species 3) Both A and B 4) None of these
Which of the following salts on dissolution of water gives pH less than 7 at 250C?
1) KCN. 2) CH3COONa 3) NaBr 4) NH4Cl
The density of 11 M solution of NaCl is 1.0585gml−1. The molality of the solution is :
1) 1.0585 2) 1.00 3) 0.10 4) 0.0585
$$3BaCl_{2}+2Na_{2}PO_{4}\rightarrow Ba_{3}(PO_{4})_{2}+6NaCl$$ Maximum amount of $$Ba_{3}(PO_{4})_{2}$$ formed when $$2$$ moles each of $$Na_{3}PO_{4}$$ and $$BaCl_{2}$$ react is:
1) 4 mol 2) 1 mol 3) 2 /3 mol 4) 5/3 mol
Nitrobenzene on reaction with conc. HNO3/H2SO4 at 80-100°C forms which one of the following products?
1) 1,2-dinitrobenzene 2) 1,3-dinitrobenzene 3) 1,4-dinitrobenzene 4) 1,2,4-trinitrobenzene
Ionic hydrides are formed by:
1) transition metals 2) elements of very high electropositivity 3) elements of very low electropositivity 4) metalloids
Which of the following process essentially follows the Markownikoff's rule?
1) Reaction of alkyl halides with dry silver oxide
2) Alkoxy mercuration demercuration of alkenes 3) Reaction of alpha−alpha−haloethers with Grignard reagent 4) All of the above
In the Fischer - Tropsch synthesis of petrol, _____and _____ are used as theraw materials.
1) CH4;H2 2) H2 ; CO 3) CH3OH;CO 4) CH4;CH3OH.
Which of the following ore is best concentrated by froth flotation method ? 1) Galena 2) Cassiterite 3) Magnetite 4) none
Which of the following can yield acetylene in one step?
1) Ethene
2) Ethylene dichloride
3) Sodium acetate
4) Propyne
Among the following, identify the species with an atom in +6 oxidation state.
1) [MnO4]− 2) [Cr(CN)6]3− 3) Cr2O3 4) CrO2Cl2
The metal carbonate that is thermally least stable is
1) BeCO3
2) BaCO3
3) CaCO3
4) MgCO3
Crystals of 100% H2?O2? is obtained treating 90% H2?O2? with:
1) solid CO2? and ether 2) dil. H2?SO4? 3) quick lime 4) NaOH+CaO
Among the following, the compounds nitrobenzene, benzene, aniline and phenol the strongest basic behaviour in acid medium exhibited by 1. phenol 2. aniline 3. nitrobenzyne 4. benzene
Mixture X containing 0.02mol of [CO(NH3)5SO4]Br and 0.02mol of [CO(NH3)Br]SO4 was prepared in 2 litre of solution . 1 litre of mixture X+ excess AgNO3→Y 1 litre of mixture X+ excess BaCl2→Z. Number of moles of Y and Z are 1) 0.01, 0.01 2) 0.02, 0.01 3) 0.01, 0.02 4) 0.02, 0.02
Which property of colloidal solution is independent of charge on the colloidal particles?
1) Coagulation 2) Electrophoresis 3) Electroosmosis 4) Tyndall effect
The pyknometric density of sodium chloride crystal is 2.165×103 kg m−3 while its X−ray density is 2.178×103 kg m−3. The fraction of unoccupied sites in sodium chloride crystal is: 1) 5.96 2) 5.96×10−2 3) 5.96×10−1 4) 5.96×10−3
The molar conductivity of acetic acid at infinite dilution is 390.7 and for 0.1 M acetic acid solution is 5.2 mho cm2 mol−1 The degree of dissociation of 0.1 M CH3COOHsolution is:
1) 13.3% 2) 0.0133% 3) 1.33% 4) 133%
The oxidation number of Pt in [Pt(C2H4)Cl3]− is:
1) +1 2) +2 3) +3 4) +4
Which of the following reacts with water at high rate? 1) Li 2) K 3) Na 4) Rb
What is the oxidation state of nitrogen in N2?O5?? 1) 5 2) 10 3) 4 4) 3
