For a certain reaction, the rate $$=\mathrm{k}[\mathrm{A}]^{2}[\mathrm{~B}]$$, when the initial concentration of A is tripled keeping concentration of $$\mathrm{B}$$ constant, the initial rate would
Identify product $$(\mathrm{A})$$ is the following reaction :
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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Helium is used to dilute oxygen in diving apparatus.
Reason R : Helium has high solubility in O$$_2$$.
In the light of the above statements, choose the correct answer from the options given below:
Amongst the following, the total number of species NOT having eight electrons around central atom in its outer most shell, is
$$\mathrm{NH}_{3}, \mathrm{AlCl}_{3}, \mathrm{BeCl}_{2}, \mathrm{CCl}_{4}, \mathrm{PCl}_{5}$$ :