On combustion of $Li$,$Na$,and $K$ in excess of air,the major oxides formed,respectively,are:

Which one of the following equations is correct for the reaction $N_{2(g)} + 3H_{2(g)} \longrightarrow 2NH_{3(g)}$?

$A$ bob of mass $m$ attached to an inextensible string of length $l$ is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed $\omega \ rad/s$ about the vertical axis. About the point of suspension:

Given that $\Delta H_f(H) = 218 \ kJ/mol$,express the $H-H$ bond energy in $kcal/mol$.

Which of the following is a dihydric alcohol?

One and a half mole of oxygen combine with aluminium to form $Al_2O_3$,then the weight of aluminium metal used in this reaction is ............. $g$ (Atomic weight of $Al = 27$)