Thermodynamically the most stable form of carbon is

The maximum value of $xy$ when $x + 2y = 8$ is

$A$ charge $q$ is placed at the centre of the line joining two equal charges $Q$. The system of the three charges will be in equilibrium if $q$ is equal to:

$A$ cyclic process $ABCDA$ is shown in the $P-V$ diagram. Which of the following curves represent the same process?

For the reaction $SnO_{2(s)} + 2H_{2(g)} \rightleftharpoons 2H_2O_{(g)} + Sn_{(l)}$,calculate $K_p$ at $900 \ K$ where the equilibrium steam-hydrogen mixture was $45\% \ H_2$ by volume.

If the normal to the curve $y(x) = \int_0^x (2t^2 - 15t + 10) dt$ at a point $(a, b)$ is parallel to the line $x + 3y = -5$ for $a > 1$,then the value of $|a + 6b|$ is equal to ...........