Which of the following compounds lacks iron?

If $\vec{a}, \vec{b}$ and $\vec{c}$ are vectors with magnitudes $2, 3$ and $4$ respectively,then the best upper bound of $|\vec{a}-\vec{b}|^2+|\vec{b}-\vec{c}|^2+|\vec{c}-\vec{a}|^2$ among the given values is

The orbital angular momentum of a $3p$ electron is

Resin and turpentine are obtained from

The enthalpy change $\left( \Delta H \right)$ for the reaction,$N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}$ is $-92.38 \ kJ$ at $298 \ K$. The internal energy change $\left( \Delta U \right)$ at $298 \ K$ is ........ $kJ$.

If ${a^x} = {b^y} = {(ab)^{xy}},$ then $x + y = $