Crystalline sodium chloride is an insulator of electricity because $......$

The solution of the differential equation $\frac{dy}{dx} - 2y \tan 2x = e^x \sec 2x$ is

The polio virus is a ..........

Which of the following aqueous solutions will exhibit the highest boiling point?

The electrons,identified by quantum numbers $n$ and $l$: $(i) n = 4, l = 1$,$(ii) n = 4, l = 0$,$(iii) n = 3, l = 2$,$(iv) n = 3, l = 1$,can be placed in order of increasing energy,from the lowest to highest,as:

$A$ particle $A$ has charge $+q$ and particle $B$ has charge $+4q$,with each of them having the same mass $m$. When allowed to fall from rest through the same electrical potential difference,the ratio of their speeds $V_A : V_B$ will be: