If $BaCl_2$ ionizes to an extent of $80 \ \%$ in aqueous solution,the value of van't Hoff factor is

Who was the first scientist to use the term 'virus' as a pathogen of infectious diseases?

$A$ particle of mass $4 m$ explodes into three pieces of masses $m, m$ and $2 m$. The equal masses move along $X$-axis and $Y$-axis with velocities $4 ms^{-1}$ and $6 ms^{-1}$ respectively. The magnitude of the velocity of the heavier mass is

When the angle of inclination of an inclined plane is $\theta$,an object slides down with uniform velocity. If the same object is pushed up with an initial velocity $u$ on the same inclined plane,it goes up the plane and stops at a certain distance on the plane. Thereafter,the body:

The correct order of the $O-O$ bond length in $O_2$,$H_2O_2$ and $O_3$ is

Which one of the following conditions is incorrect for a well-behaved wave function $(\psi)$?