Which of the following is an opiate narcotic?

In an electroplating experiment,$m \, g$ of silver is deposited when $4 \, A$ of current flows for $2 \, min$. The amount (in $g$) of silver deposited by $6 \, A$ of current for $40 \, s$ will be

The basis of the quantum mechanical model of an atom is

If $|x| < \frac{1}{2}$,then the coefficient of $x^r$ in the expansion of $\frac{1+2x}{(1-2x)^2}$ is

What is a species?

Which of the following reactions is possible at the anode?