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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.
Concept: Temperature Dependence of the Rate of a Reaction
For a reaction R ---> P, half-life (t1/2) is observed to be independent of the initial concentration of reactants. What is the order of reaction?
Concept: Factors Influencing Rate of a Reaction
Define the following term:
Pseudo first-order reaction
Concept: Factors Influencing Rate of a Reaction
For a reaction
\[\ce{2H2O2->[I^-][Alkaline medium]2H2O + O2}\]
The Proposed mechanism is given below:
(1) H2O2+I- → H2O+IO-(slow)
(2) H2O2+IO-→H2O+I-+O2(fast)
(i) Write the rate law for the reaction.
(ii) Write the overall order of a reaction.
(iii) Out of steps(1) and (2), which one is the rate-determining step?
Concept: Effect of Catalyst on the Rate of Reaction
The decomposition of NH3 on a platinum surface is a zero-order reaction. If the rate constant (k) is 4 x 10-3 ms-1, how long will it take to reduce the initial concentration of NH3 from 0.1 M to 0.064 M?
Concept: Zero Order Reactions
What are interstitial compounds?
Concept: Physical Properties of the Transition Elements (d-block)
Define lanthanoid contraction.
Concept: F-block Elements >> The Lanthanoids
Account for the following :
Zr and Hf have almost similar atomic radii.
Concept: F-block Elements >> The Lanthanoids
Complete the following equations : 2 MnO2 + 4 KOH + O2 →
Concept: Important Compounds of Transition Elements
Complete the following equations : 2 Na2CrO4 + 2 H + →
Concept: Important Compounds of Transition Elements
|
`E_((M^(2+)/M)` |
Cr | Mn | Fe | Co | Ni | Cu |
| -0.91 | -1.18 | -0.44 | -0.28 | -0.25 | -0.34 |
From the given data of E0 values, answer the following questions :
(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive
(2) Why is `E_(((Mn^(2+))/(Mn)))` value is highly negative as compared to other elements
(3) Which is the stronger reducing agents Cr2+ or Fe2+ ? Give Reason.
Concept: Physical Properties of the Transition Elements (d-block)
Why do actinoids show a wide range of oxidation states?
Concept: F-block Elements >> The Actinoids
Write on similarity between the chemistry of lanthanoids and actinoids.
Concept: F-block Elements >> The Actinoids
Explain effects of lanthanoid contraction.
Concept: F-block Elements >> The Lanthanoids
Write the formula of an oxo-anion of Manganese (Mn) in which it shows the oxidation state equal to its group number.
Concept: Important Compounds of Transition Elements
Answer the following question.
When MnO2 is fused with KOH in the presence of KNO3 as an oxidizing agent, it gives a dark green compound (A). Compound (A) disproportionates in an acidic solution to give a purple compound (B). An alkaline solution of compound (B) oxidizes KI to compound (C) whereas an acidified solution of compound (B) oxidizes KI to (D). Identify (A), (B), (C), and (D).
Concept: Important Compounds of Transition Elements
Using IUPAC norms, write the formula of potassium trioxalatochromate(III).
Concept: Important Compounds of Transition Elements
Give reasons for the following statement:
Transition metals and most of their compounds show paramagnetic behaviour.
Concept: Physical Properties of the Transition Elements (d-block)
Give reason for the following statement:
Physical and chemical properties of the 4d and 5d series of the transition elements are quite similar to expected.
Concept: Physical Properties of the Transition Elements (d-block)
Define transition metals.
Concept: Electronic Configurations of the d-block Elements
