Class 12 Chemistry - Chapter Chemical Kinetics NCERT Solutions | For the reaction: 2A + B → A2B
For the reaction:
2A + B → A2B
the rate = k[A][B]2with k= 2.0 x 10-6mol-2L2s-1. Calculate the initial rate of the reaction when [A] = 0.1 mol L-1, [B] = 0.2 mol L-1. Calculate the rate of reaction after [A] is reduced to 0.06 mol L-1.
The initial rate of the reaction is
Rate = k [A][B]2
= (2.0 × 10 - 6mol - 2L2s - 1) (0.1 mol L - 1) (0.2 mol L - 1)2
= 8.0 × 10 - 9mol - 2L2s - 1
When [A] is reduced from 0.1 mol L - 1to 0.06 mol - 1, the concentration of A reacted = (0.1 - 0.06) mol L - 1 = 0.04 mol L - 1
Therefore, concentration of B reacted= 1/2 x 0.04 mol L-1 = 0.02 mol L - 1
Then, concentration of B available, [B] = (0.2 - 0.02) mol L - 1
= 0.18 mol L - 1
After [A] is reduced to 0.06 mol L - 1, the rate of the reaction is given by,
Rate = k [A][B]2
= (2.0 × 10 - 6mol - 2L2s - 1) (0.06 mol L - 1) (0.18 mol L - 1)2
= 3.89 mol L - 1s - 1
More Questions From Class 12 Chemistry - Chapter Chemical Kinetics
- Q:-
The half-life for radioactive decay of 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living tree. Estimate the age of the sample.
- Q:-
For a first order reaction, show that time required for 99% completion is twice the time required for the completion of 90% of reaction.
- Q:-
The rate of a reaction quadruples when the temperature changes from 293 K to 313 K. Calculate the energy of activation of the reaction assuming that it does not change with temperature.
- Q:-
A first order reaction takes 40 min for 30% decomposition. Calculate t1/2.
- Q:-
In a reaction, 2A → Products, the concentration of A decreases from 0.5 mol L-1 to 0.4 mol L-1 in 10 minutes. Calculate the rate during this interval?
- Q:-
The conversion of molecules X to Y follows second order kinetics. If concentration of X is increased to three times how will it affect the rate of formation of Y?
- Q:-
During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1μg of 90Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.
- Q:-
Sucrose decomposes in acid solution into glucose and fructose according to the first order rate law, with t1/2 = 3.00 hours. What fraction of sample of sucrose remains after 8 hours?
- Q:-
The decomposition of A into product has value of k as 4.5 x 103 s-1 at 10°C and energy of activation 60 kJ mol-1. At what temperature would k be 1.5 x 104 s-1?
- Q:-
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
Popular Questions of Class 12 Chemistry
- Q:-
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
- Q:-
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
- Q:-
Why are solids rigid?
- Q:-
Write any two characteristics of Chemisorption.
- Q:-
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
- Q:-
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
- Q:-
Why are pentahalides more covalent than trihalides?
- Q:-
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
- Q:-
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
- Q:-
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
Recently Viewed Questions of Class 12 Chemistry
- Q:-
What happens when PCl5 is heated?
- Q:-
Explain how much portion of an atom located at
(i) corner and
(ii) body-centre
of a cubic unit cell is part of its neighbouring unit cell.
- Q:-
What happens when sulphur dioxide is passed through an aqueous solution of Fe(III) salt?
- Q:-
Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
- Q:-
An element with molar mass 2.7 x 10-2kg mol-1 forms a cubic unit cell with edge length 405 pm. If its density is 2.7 x 103 kg m-3, what is the nature of the cubic unit cell?
- Q:-
How is O3 estimated quantitatively?
- Q:-
Accomplish the following conversions:
(i) Nitrobenzene to benzoic acid
(ii) Benzene to m-bromophenol
(iii) Benzoic acid to aniline
(iv) Aniline to 2,4,6-tribromofluorobenzene
(v) Benzyl chloride to 2-phenylethanamine
(vi) Chlorobenzene to p-chloroaniline
(vii) Aniline to p-bromoaniline
(viii) Benzamide to toluene
(ix) Aniline to benzyl alcohol.
- Q:-
Write equations of the following reactions:
(i) Friedel-Crafts reaction-alkylation of anisole.
(ii) Nitration of anisole.
(iii) Bromination of anisole in ethanoic acid medium.
(iv) Friedel-Craft's acetylation of anisole.
- Q:-
Action of soap is due to emulsification and micelle formation. Comment.
- Q:-
How the following conversions can be carried out?
(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
4 Comment(s) on this Question
oohhhooo AHhhaa
How come we halved the concentration of A to find the new one of B
Ohho
Second part of this answer\'s method is correct but answer is wrong...it will be = 3.888*10^-9 mol-2L2s-1
- All Chapters Of Class 12 Chemistry
- All Subjects Of Class 12