Assuming complete ionisation,the $pH$ of $0.1 \ M \ HCl$ is $1$. The molarity of $H_2SO_4$ with the same $pH$ is (in $M$)

$A$ plane passes through the point $A(2, 1, -3)$. If the distance of this plane from the origin is maximum,then its equation is:

Pure ammonia is placed in a vessel at a temperature where its dissociation constant $(\alpha)$ is appreciable. At equilibrium,

The number of tetrahedral voids present in $0.5 \text{ mole}$ of $HCP$ crystal structure is:

$A$ black body radiates energy at the rate of $E \text{ W/m}^2$ at a high temperature $T \text{ K}$. When the temperature is reduced to $\left(\frac{T}{2}\right) \text{ K}$,the radiant energy is

If $ax^2-34xy-5y^2+2x+26y-5=0$ represents a pair of straight lines,then the value of $a$ is