Question

What is 1M $\mathrm{NaOH}$?

Answer 1

1. M is denoted for molarity.
2. Molarity is defined as number of moles per liter of solution.
3. Molarity is given by
   $$\begin{gathered} \mathrm{M}=\frac{\mathrm{n}}{\mathrm{V}} \\ \mathrm{where},\mathrm{M}\mathrm{is}\mathrm{the}\mathrm{molarity} \\ \mathrm{n}\mathrm{is}\mathrm{the}\mathrm{number}\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{solute} \\ \mathrm{V}\mathrm{is}\mathrm{the}\mathrm{volume}\mathrm{of}\mathrm{solution}(\mathrm{in}\mathrm{L}) \end{gathered}$$
4. 1M solution means 1 mole of a substance per liter of solution.
5. Therefore, 1M $\mathrm{NaOH}$ means 1 mole of $\mathrm{NaOH}$ per liter of solution.