One mole of calcium phosphide on reaction with excess water gives

If $\alpha$ and $\beta$ are the roots of the equation $x^2-2x+4=0$,then $\alpha^9+\beta^9$ is equal to

Under which one of the following conditions do real gases approach the ideal gas behaviour?

Which of the following statements is correct for any thermodynamic system?

Consider the set of all triangles $OPQ$ where $O$ is the origin and $P$,$Q$ are distinct points in the plane with non-negative integral coordinates $(x, y)$ such that $5x + y = 99$. The number of such distinct triangles whose area is a positive integer is:

Which of the following is the composition of a virus?