In the hardening stage of plaster of Paris,the compound formed is:

If $2x + 3y + 12 = 0$ and $x - y + 4\lambda = 0$ are conjugate with respect to the parabola $y^2 = 8x$,then $\lambda$ is equal to

In the isoelectronic series of metal carbonyls,the $CO$ bond strength is expected to increase in the order:

The solution of $x \frac{dy}{dx} = y + x e^{y/x}$ with $y(1) = 0$ is

The solution of $(x^2+y^2) dx = 2xy dy$ is:

Consider the following reaction equilibrium:
$N_{2(g)} + 3H_{2(g)} \rightleftharpoons 2NH_{3(g)}$
Initially,$1 \text{ mole}$ of $N_2$ and $3 \text{ moles}$ of $H_2$ are taken in a $2 \text{ L}$ flask. At equilibrium state,if the number of moles of $N_2$ is $0.6$,what is the total number of moles of all gases present in the flask?