Conductivity of strong and weak acids and bases, and of their salts.

Provide labeled (48pt) museum jars containing 150mL each of 0.01M:

[ print labels ]

SA - HCl
WA - HAc
H₂O
WB - NH₃
SB - NaOH

Provide additional labels:

+ NaOH
+ NH₃

Preparation:

To each of the five museum jars, add 150 mL water and 0.75 mL of universal indicator. Add 1.5 mL of each 1M acid/base stock solution as indicated by the labels. The water sample should be increased to 3/4 jar capacity, as it will be used for an electrode rinse.

Concentrations of solutions should be adjusted so that the salts made by mixing solutions (as indicated by additional labels) will result in ~pH 7.0 (green UnivIndic.).

Measure conductivity of the contents of the five museum jars, noting pH indicated by color. Mix entire contents of jars as suggested by labels (that is, NaOH -> HCl, NH3 -> HAc). First note color, then conductivity of strong acid/base salt. Then note color and conductivity of weak acid/base salt.