Q: Hydrolysis of sucrose is given by the following reaction.Sucrose + H2O⇋ Glucose FructoseIf the equilibrium constant (Kc) is 2—1013 at 300 K, the value of △rG⊖ at the same temperature will be :

△G=△Gº+RTlnQ At equilibrium △G=0,Q=Keq So △rGº=−RTlnKeq △rGº=−8.314Jmol−1K−1×300K×ln(2×1013)

Q: An element has a body centered cubic (bcc) structure with a cell edge of 288 pm. The atomic radius is:

For BCC,3a=4r a= edge lengthr=43a r= radiusGiven, a= 288 pmr=43×288 pm

Q: The freezing point depression constant (Kf) of benzene is 5.12 K kg mol−1. The freezing point depression for the solution of molality 0.078 m containing a non-electrolyte solute in benzene is (rounded off upto two decimal places):

Depression in freezing point is given by-ΔTf=kfmGiven, kf=5.12 K kg mol−1 and m=0.078 mol kg−1By using the formula,=0.399 K≈0.40 KSo, ΔTf=0.40 K

Question 1

Hydrolysis of sucrose is given by the following reaction.Sucrose + H2​O⇋ Glucose FructoseIf the equilibrium constant (Kc​) is 2—1013 at 300 K, the value of △r​G⊖ at the same temperature will be :

Accepted Answer

△G=△Gº+RTlnQ At equilibrium △G=0,Q=Keq​ So △r​Gº=−RTlnKeq​ 	  △r​Gº=−8.314Jmol−1K−1×300K×ln(2×1013)

Question 2

An element has a body centered cubic (bcc) structure with a cell edge of 288 pm. The atomic radius is:

Accepted Answer

For BCC,3​a=4r 						a= edge lengthr=43​a​ 						r= radiusGiven, a= 288 pmr=43​​×288 pm

Question 3

On electrolysis of dil. sulphuric acid using Platinum (Pt) electrode, the product obtained at anode will be:

Accepted Answer

During the electrolysis of dil. sulphuric acid using Pt electrodes following reaction will take place.At cathode :		4H+(aq)+4e−⟶2H2​(g) At anode :		2H2​O(I) → O2​(g)+4H+(aq)+4e−

Question 4

Which of the following oxoacid of sulphur has “OO“ linkage?

Accepted Answer

Peroxodisulfuric acid

Question 5

Which of the following amine will give the carbyle test?

Accepted Answer

Aliphatic and aromatic primary es give carbylamine reaction.

Question 6

The calculated spin only magnetic moment of Cr2+ ion is:

Accepted Answer

Electronic configuration of Cr – [Ar] 3d54s1 Electronic configuration of Cr2+ – [Ar] 3d4  Number of unpaired e−=4 Spin only magnetic moment = n(n+2)​ n = number of unpaired e− Spin only magnetic moment 	=4(4+2)​ =24​ BM=4.9 BM

Question 7

The freezing point depression constant (Kf​) of benzene is 5.12 K kg mol−1. The freezing point depression for the solution of molality 0.078 m containing a non-electrolyte solute in benzene is (rounded off upto two decimal places):

Accepted Answer

Depression in freezing point is given by-ΔTf​=kf​mGiven, kf​=5.12 K kg mol−1 and m=0.078 mol kg−1By using the formula,=0.399 K≈0.40 KSo, ΔTf​=0.40 K

Question 8

The number of Faradays(F) required to produce 20 g of calcium from molten CaCl2​ (Atomic mass of Ca = 40 g mol−1) is

Accepted Answer

1 equivalent of any substance is deposited by 1 F of charge.We have, 20 g calciumNumber of equivalents = Equivalent massGiven mass​ = 2020​=1 Equivalent mass of Ca = 240​=20 So, 1 faraday of charge is required.

Question 9

Reaction between benzaldehyde and acetophenone in presence of dilute NaOH is known as:

Accepted Answer

In the presence of dil. OH(−), benzaldehyde and acetophenone will react to undergo cross-aldol condensation.

Question 10

An increase in the concentration of the reactants of a reaction leads to change in:

Accepted Answer

Heat of reaction is an extensive property. Hence, on change of amount/concentration of reactants heat of reaction changes.

Question 11

Identify the correct statement from the following :

Accepted Answer

The iron obtained from blast furnace contains about 4% carbon and many impurities like S, P, Si, Mn in smaller amount. This is known as pig iron and cast into variety of shapes.

Question 12

Which of the following is a cationic detergent?

Accepted Answer

Cetyltrimethylammonium bromide

Question 13

The mixture which shows positive deviation from Raoult's law is:

Accepted Answer

Pure ethanol molecules are hydrogen bonded. On adding acetone, its molecules get in between the ethanol molecules and break some of the hydrogen bonds between them. This weakens the intermolecular attractive interactions and the solution shows positive deviation from Raoult's law.

Question 14

Which of the following is the correct order of increasing field strength of ligands to form coordination compounds?

Accepted Answer

Spectrochemical series (as given in NCERT) :

Question 15

Which of the following is a basic acid ?

Accepted Answer

(Structure of Lysine)Lysine is a basic o acid.

Question 16

Which of the following is a natural polymer?

Accepted Answer

Naturally occuring polymer, natural rubber is cis-1, 4– polyisoprene

Question 17

Sucrose on hydrolysis gives:

Accepted Answer

SurcoseHydrolysis​α−D−Glucose+β−D−Fructose

Question 18

The following metal ion activates many enzymes, participates in the oxidation of glucose to produce ATP and with Na, is responsible for the transmission of nerve signals.

Accepted Answer

Potassium (K) activates many enzymes participate in oxidation of glucose to produce ATP and helps in the transmission of nerve signal along with Na.

Question 19

Identify the incorrect statement.

Accepted Answer

Oxidation state of Cr in CrO42−​ and Cr2​O72−​ is +6

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