Which of the following curve represents the first order reaction?
Show Hint
- Graph (A)
- Graph (B)
- Graph (C)
- Graph (D)
The Correct Option is A
Solution and Explanation
For a first order reaction the rate depends directly on the concentration of the reactant, that is rate = k[A]. So if we plot rate on the y-axis against concentration on the x-axis, we get a straight line that passes through the origin.
Step 1:
Check each curve. A reaction is first order only when the graph shows a straight line relationship that fits rate = k[A] (a line through the origin), or an exponential decay of concentration with time.
Step 2:
The curve that shows a straight line passing through the origin for rate versus concentration is the correct one, because it matches rate = k[A].
Answer: Option (A) is the curve that represents a first order reaction.
Top CBSE CLASS XII Chemistry Questions
- ${AgNO_3}$ does not decompose where :
- Azeotropic mixture of water and HCl boils at 381.5 K. By distilling the mixture it is possible to obtain
Write IUPAC names of the following compounds and classify them into primary, secondary and tertiary amines.
(i) (CH3 )2CHNH2 (ii) CH3 (CH2 )2NH2 (iii) CH3NHCH(CH3 )2
(iv) (CH3 )3CNH2 (v) C6H5NHCH3 (vi) (CH3CH2 )2NCH3 (vii) m–BrC6H4NH2
Give one chemical test to distinguish between the following pairs of compounds.
(i) Methylamine and dimethylamine
(ii) Secondary and tertiary amines
(iii) Ethylamine and aniline
(iv) Aniline and benzylamine
(v) Aniline and N-methylanilineAccount for the following:
(i) pKb of aniline is more than that of methylamine.
(ii) Ethylamine is soluble in water whereas aniline is not.
(iii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide.
(iv) Although amino group is o– and p– directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.
(v) Aniline does not undergo Friedel-Crafts reaction.
(vi) Diazonium salts of aromatic amines are more stable than those of aliphatic amines. (vii) Gabriel phthalimide synthesis is preferred for synthesising primary amines.
Top CBSE CLASS XII Chemical Kinetics Questions
- The following data were obtained during the first order thermal decomposition of \(SO_2Cl_2\) at a constant volume.
\(SO_2Cl_2(g) → SO_2(g) + Cl_2(g)\)Calculate the rate of the reaction when total pressure is 0.65 atm.Experiment Time/s-1 Total pressure/atm 1 0 0.5 2 100 0.6 The rate constant for the decomposition of \(N_2O_5\) at various temperatures is given below:
T/°C 0 20 40 60 80 105 x k/s-1 0.0787 1.70 25.7 178 2140 Draw a graph between ln k and \(\frac 1T\) and calculate the values of \(A\) and \(E_a\).
Predict the rate constant at 30 ºC and 50 ºC.The rate constant for the decomposition of hydrocarbons is 2.418 x 10-5 s-1 at 546 K. If the energy of activation is 179.9 kJ/mol, what will be the value of pre-exponential factor.
Consider a certain reaction \(A\) \(→\) \(Products\) with \(k = 2.0 \times 10^{-2 }s^{-1}\) . Calculate the concentration of A remaining after 100 s if the initial concentration of A is 1.0 mol L-1.
Sucrose decomposes in acid solution into glucose and fructose according to the first order rate law, with \(t_{\frac 12} = 3.00\ hours\). What fraction of sample of sucrose remains after \(8 \ hours\)?
Top CBSE CLASS XII Questions
- 2, b, c are in A.P. and the range of determinant $\begin{vmatrix}1&1&1\\ 2&b&c\\ 4&b^{2}&c^{2}\end{vmatrix}$ is [2, 16]. Then find range of c is
- A boy of mass 50 kg is standing at one end of a, boat of length 9 m and mass 400 kg. He runs to the other, end. The distance through which the centre of mass of the boat boy system moves is
- A capillary tube of radius r is dipped inside a large vessel of water. The mass of water raised above water level is M. If the radius of capillary is doubled, the mass of water inside capillary will be
- A circular disc is rotating about its own axis. An external opposing torque 0.02 Nm is applied on the disc by which it comes rest in 5 seconds. The initial angular momentum of disc is
- A circular disc is rotating about its own axis at uniform angular velocity \(\omega.\) The disc is subjected to uniform angular retardation by which its angular velocity is decreased to \(\frac {\omega}{2}\) during 120 rotations. The number of rotations further made by it before coming to rest is