Video Transcript
Why is it not possible to
distinguish between ammonium acetate and sodium chloride solutions using pH
indicators?
Firstly, pH indicators have
different colors in particular pH ranges, depending on the indicator. They are therefore useful for
showing solutions have different pHs. Ammonium acetate is a combination
of the ions ammonium and acetate. Ammonium is a weak acid, and the
acetate anion is a weak base. The effect of these two ions in
solution cancel out roughly, and the solution is overall neutral, with a pH of about
seven.
Sodium chloride in solution
dissociates to form sodium+ and Cl– ions. These ions are both neutral in
solution. Therefore, the solution is neutral
and the pH is equal to seven. Since these two solutions would
have the same pH, pH indicators would be the same color and therefore would not
differentiate one from the other.
Therefore, it is not possible to
distinguish between ammonium acetate and sodium chloride solutions using pH
indicators because the two salt solutions are neutral and therefore have the same
pH. Therefore, pH indicators would have
the same color in both solutions.
