# What colour change would NaCl(aq) cause to added litmus paper?

Litmus paper may change colour depending on the pH of the solution in which it is placed. We has $N a C l \left(a q\right)$, which as the salt of a strong acid and strong base does not affect aqueous $p H$,
On the other hand, if we examined the $p H$ of say $N a F \left(a q\right)$, we would find that the solution was SLIGHTLY basic due to the hydrolytic action of the fluoride ion:
${F}^{-} + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s H F \left(a q\right) + H {O}^{-}$