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What happens when SiO2 reacts with NaOH?

Solution: Silicon dioxide act as weak acid. When Silicon dioxide (SiO2) reacts with hot and concentrated sodium hydroxide to form sodium... View Article

pKa of acetic acid is 4.74. The concentration of CH3COONa is 0.01M. The pH of CH3COONa solution is?

Solution: CH3COONa is a salt of weak acid CH3COOH and strong base NaOH. CH3COONa + H2O ⇋ CH3COOH + Na+ + OH- This is the case of salt... View Article

N2(g)+3H2(g)⇌2NH3(g) for the reaction initially the mole ratio was 1:3 of N2:H2. At equilibrium 50% of each has reacted. If the equilibrium pressure is p, the partial pressure of NH3 at equilibrium is

Solution: N2(g) + 3H2(g) ⇌ 2NH3(g) At initial : a 3a 0 At... View Article

Out of N, O, Ne, Na, Na^(+) select the species which have maximum and minimum ionization energy.

Solution: Ionization energy: ionization energy as the minimum energy that an electron in a gaseous atom or ion is required to remove an electron... View Article

Compound PdCl4.6H2O is a hydrated complex; 1 m aqueous solution of it has freezing point 269.28 K. Assuming 100% ionization of complex, calculate the number of ions furnished by the complex in the solution. (Kf for water = 1.86K kg mol−1)

Solution: ΔTf =Kf × molality × i Where ΔTf = Depression of freezing point , i= vant Hoff's factor ΔTf =273−269⋅28 ΔTf = 3⋅72 3⋅72 =1⋅86 ×... View Article

which of the following pairs will give chlorine gas most quickly, upon reaction? (A) HCl and KMnO4 (B) NaCl and H3PO4 (C) NaCl and MnO2 (D) CaCl2 and Br2

Solution: (a) HCl and KMnO4 KMnO4 is a good oxidizing agent, It oxidised HCl quickly to produce Cl2 gas 2KMnO4(s) + 16HCl(aq) → 2KCl(aq) +... View Article

Hydrolysis of sucrose is given by the following reaction Sucrose+H2O⇌Glucose+Fructose If the equilibrium constant (KC) is 2×10^13 at 300K, the value of ΔrG⊝at the same temperature will be :

Solution: The relation between Gibbs energy and equilibrium constant is given by, ΔG0=−RT lnKc Where ΔG0 = Standard gibbs energy Kc =... View Article

For the decomposition of N2O5 it is given that: 2N2O5 (g) → 4NO2 (g) + O2 (g), Activation energy Ea N2O5 (g) → 2NO2 (g) + ½ O2 (g), Activation energy Ea’ then, (a) Ea = Ea’ (b) Ea > Ea’ (c) Ea < Ea’ (d) Ea = 2Ea’

Solution: 2N2O5 (g) → 4NO2 (g) + O2 (g), Activation energy = Ea N2O5 (g) → 2NO2 (g) + ½ O2 (g), Activation energy Ea’ Activation... View Article

XeF6 cannot be handled in a glass vessel, because it reacts with SiO2 forming

Solution: XeF6 cannot be stored in quartz or silica vessel because it react with SiO2 form an explosive compound of XeO3. The reactions are... View Article

Classify the following as amorphous or crystalline solids: Polyurethane, Naphthalene, Benzoic acid, Teflon, Potassium nitrate, Cellophane, Polyvinyl Chloride, Fiberglass, and Copper

In crystalline solids the particles are arranged in a 3 dimensional order. Amorphous has irregular arrangement of solid... View Article

which of the following ore contains two metals which show diagonal relationship? (a) Na and Mg (b) Li and Mg (c) Li and Na (d)Al and C

Solution (B) A diagonal relationship is said to exist between certain pairs of diagonally adjacent elements in the second and third periods of... View Article

An organic compound (C3H9N)(A), when treated with nitrous acid, gave an alcohol and N2 gas was evolved. (A) on warming with CHCl3 and caustic potash gave (C) which on reduction gave isopropylmethyl amine. Predict the structure of (A)

Solution: An organic compound (C3H9N)(A), when treated with nitrous acid, gave an alcohol and N2 gas was evolved. It should be a primary... View Article

Which among MeX,RCH2X,R2CHX,R3CX is most reactive towards SN2 reaction?

Solution: SN2 reaction mechanism requires the attack of nucleophile from the back side of the carbon atom. So the product assumes a... View Article

For the following reaction, the mass of water produced from 445g of C57H110O6 is: 2C57 H110 O6 (s) +163O2 (g) →114CO2 (g)+110H2O(l)

Solution: In the equation: 2C57H110O6 (s) + 163O2 (g) → 114CO2 (g) + 110 H2O(l) The weight of C57H110O6 is taken 445 g. Molecular weight of... View Article

In which form plants do absorb boron?

Boron is absorbed by the plants mainly as boric acid and also as borate ions. Boron is released by withering of rock minerals. Boron uptake is... View Article

The average thermal energy for a mono-atomic gas is (kb is boltzmann constant and t, absolute temperature)

Solution: In the mono atomic gas the total degree of freedom = 3 (translational degree of freedom) The average thermal energy for a mono-atomic... View Article

CH3CN + 4[H] in presence of Na/C2H5OH gives

Solution: This reaction is known as Mendius reaction. In thisreaction an organic nitrile is reduced by nascent hydrogen in presence of sodium... View Article

Rahul forgot to add the reaction mixture to the round bottomed flask at 27 degree celsius but instead he placed the flask on the flame. After a lapse of time, he realized his mistake, and using a pyrometer he found the temperature of the flask was 477 degree celcius. What fraction of air would have been expelled out?

Solution: The initial temperature T1 =27oC = 27+273K = 300K The final temperature T2 = 477oC = 477+273K= 750K The inital volume is V1 and the... View Article

At STP, the density of nitrogen monoxide is ?

Solution: S.T. P = Standard Temperature and Preesure The Molecular weight of NO = 14 + 16 = 30 gm AT STP 1 mole of gas occupy volume= 22.4L... View Article

The sum of number of σ bonds and π bonds present in P4O10 is

Solution: In the structure of P4O10 the number of sigma bond = 16 The number of pi bond = 4 The sum of number of σ bonds and π bonds present... View Article

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