HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Important Questions for Chemistry

Show that the time required for 99.9% completion of a first-order reaction is three times the time required for 90% completion.

How will you determine activation energy from rate constants at two different temperatures?

Answer the following in brief.

Give one example and explain why it is pseudo-first-order.

The rate law relates to the rate of a chemical reaction in terms of _______.

For first order reaction, the rate constant for the decomposition of N₂O₅ is 6 × 10^–4 s ^–1. The half-life period for decomposition in seconds is ______.

Effect of catalyst in a chemical reaction is to change the _______.

Give one example of a pseudo first-order reaction.

Explain pseudo first order reaction with a suitable example.

Explain with the help of a potential energy diagram that the catalyst increases the rate of the reaction.

Why is molecularity applicable for only elementary reactions whereas order of a reaction is applicable for elementary and complex reactions? Explain with suitable examples.

For a zero-order reaction, molecularity can never be equal to zero. Explain.

For the reaction 2A + B → C, rate of disappearance of A 0.076 mol s ^–1.

1. What is the rate of formation of C?
2. What is the rate of consumption of B?
3. What is the rate of the overall reaction?

In a first-order reaction A → B, 60% of a given sample of a compound decomposes in 45 mins. What is the half-life of reaction? Also, write the rate law equation for the above first-order reaction.

Derive integrated rate law for a zero-order reaction \[\ce{A -> Product}\].

Identify the molecularity of following elementary reaction:

NO_(g) + O_3(g) → NO_3(g) + O_(g)

Obtain the expression for half-life and rate constant of the first-order reaction.

Define the half-life of a first-order reaction.

Which of the following correctly represents integrated rate law equation for a first order reaction in a gas phase?

Derive integrated rate law for zero order reaction.

What is the rate constant?