At $90 \, ^\circ C$,the concentration of $[H_3O^+]$ in pure water is $10^{-6} \, M$. What is the value of $K_w$ at this temperature?

In which of the following reactions does hydrogen act as an oxidizing agent?

Which of the following statements is true regarding the industrial production of hydrogen gas from water gas $(CO + H_2)$?

If $\frac{d^2y}{dx^2} + \sin x = 0$,then the solution of the differential equation is:

The reagent used for converting acetylene to oxalic acid is

$A$ candidate takes three tests in succession and the probability of passing the first test is $p$. The probability of passing each succeeding test is $p$ if he passes the preceding one,or $\frac{p}{2}$ if he fails the preceding one. The candidate is selected if he passes at least two tests. The probability that the candidate is selected is: