For a reaction,$A + B^{2+} \rightarrow B + A^{2+}$; $E^{\circ} = 0.2955 \ V$. Hence,the equilibrium constant of the reaction at $25^{\circ}C$ is:

Which of the following is $NOT$ a characteristic of angiosperms?

Degenerate electron pressure will not be sufficient to prevent core collapse of a white dwarf if its mass becomes $n$ times the solar mass. The value of $n$ is:

In the circuit shown in the figure below, which of the following statements is incorrect?

$A$ 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:

Consider the following reaction: $N_{2(g)} + 3H_{2(g)} \longrightarrow 2NH_{3(g)}$. The rate of this reaction in terms of $N_2$ at $T \ K$ is $-\frac{d[N_2]}{dt} = 0.02 \ mol \ L^{-1} \ s^{-1}$. What is the value of $-\frac{d[H_2]}{dt}$ (in units of $mol \ L^{-1} \ s^{-1}$) at the same temperature?