MEDIUM
JEE Main
IMPORTANT
Earn 100

An aqueous solution containing 288 g of a non-volatile compound, having composition CnH2nOn in 90 g of water, boils at 101.24°C at 1 atm pressure. What is the molecular formula of the compound? Kb=0.512°C/m

Important Questions on Miscellaneous Problems for Revision

MEDIUM
JEE Main
IMPORTANT

Although AgCl is insoluble in water, it readily dissolves upon the addition of ammonia AgCl (s)+2NH3 (aq)AgNH32+ (aq)+Cl- (aq)

What is the equilibrium constant for this dissolving process? (Report your answer after multiplying by 1000)

Ksp(AgCl)=1.8×10-10 and  KfAgNH32+=1.7×107

HARD
JEE Main
IMPORTANT

Although AgCl is insoluble in water, it readily dissolves upon the addition of ammonia. AgCl(s)+2NH3(aq)AgNH32+(aq)+Cl-(aq)

Ammonia is added to a solution containing an excess of AgCl (s). The final volume is 1l, and the resulting equilibrium concentration of NH3 is 0.80 M. Calculate the number of moles of AgCl dissolved, the molar concentration of AgNH32+ , and the number of moles of NH3 added to the original solution.

Ksp(AgCl)=1.8×10-10 and KfAgNH32+=1.7×107

MEDIUM
JEE Main
IMPORTANT

From the dissociation constants, Ka and Kb for an acid and its conjugate base, show that Ka·Kb=Kw.

MEDIUM
JEE Main
IMPORTANT

The tallest trees known are the redwoods in California. Assuming the height of a redwood tree to be 105 m, estimate the osmotic pressure required to push water up from the roots to the treetop. dH2O=1 g/cc, g=9.8 m s-2

If the answer is of type y×106 Pa, mention the value of y correct up to nearest integer value.

MEDIUM
JEE Main
IMPORTANT

A sample of impure cuprite, Cu2O, contains 66.6% copper. Calculate the percentage of pure Cu2O in the sample. Cu=63.5, O=16

Round-off your answer to the nearest integer.

MEDIUM
JEE Main
IMPORTANT

How much of Ag+would remain in the solution after mixing equal volumes of 0.08 M AgNO3 and 0.08 M HOCN ? Ka (HOCN)=3.3×10-4  Ksp (AgOCN)=2.3×10-7

If the answer is of type y×10-4 M, report the value of y correct up to nearest integer value.

HARD
JEE Main
IMPORTANT

The following equilibrium was studied by analysing the equilibrium mixture for the amount of HCl produced

LaCl3 (s)+H2O (g)LaOCl (s)+2HCl (g)

A vessel whose volume was 1.25 litre was filled with 0.0125 mole of lanthanum (III) chloride and 0.025 mole of water. After the mixture came to equilibrium in a closed vessel at 619°C, the gaseous mixture was removed and dissolved in more water. Sufficient silver (I) ion was added to precipitate the chloride ions completely, as silver chloride. If  3.59 g of AgCl was obtained, what is the value of Kc at  619°C?

HARD
JEE Main
IMPORTANT
A solution is 0.10 M Co2+and 0.10 M Hg2+. Calculate the range of pH in which only one of the metal sulphides precipitates when the solution is saturated in H2S.Ksp (CoS)=4×10-21 and Ksp (HgS)=1.6×10-52