Chemistry in Everyday Life — Chemistry STD 12 — Question

Consider the following statements.
(i) The action of catalytic poison occurs when the poison blocks the active centres of the catalyst.
(ii) A promoter decreases the number of active centres on the surfaces.
(iii) Increase in the activity of a catalyst by increasing the surface area.
Which of the above statement is / are correct?

Which one of the following is a permanent gas?

The metal used for galvanisation of iron is ……………

The pH of the battery acid is ………….

Consider the following statements.
(i) Rate of the reaction does not depend on the initial concentration of the reactants.
(ii) Rate constant of the reaction depends on the initial concentration of reactants.
(iii) Rate constant of the reaction is equal to the rate of the reaction, when the concentration of each of the reactants is unity.
Which of the above statement(s) is / are not correct?

Which one of the following is an example for nitro arenes?

Find out crystalline allotrophic form of sulphur?

Consider the following statements.
(i) The outer sphere in coordination compound is called ionisation sphere.
(ii) The primary valences are non directional while secondary valences are directional.
(iii) The primary valances of a metal ion is negative and it is satisfied by positive ions.
Which of the above statements is/are not correct? .