The conductivity of centimolar solution of $$\mathrm{KCl}$$ at $$25^{\circ} \mathrm{C}$$ is $$0.0210 ~\mathrm{ohm}^{-1} \mathrm{~cm}^{-1}$$ and the resistance of the cell containing the solution at $$25^{\circ} \mathrm{C}$$ is $$60 ~\mathrm{ohm}$$. The value of cell constant is -
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: