The ph value

THE PH VALUE & THE ELECTRICAL CONDUCTIVITY OF A SOLUTION JOOYEON PARK AIM To know how to check the PH value of a solution and to see the relationship between the PH value and the electrical conductivity. MATERIALS Universal indicator, litmus, phenolphthalein, water, 6 beakers, wires, light bulbs, test tubes, metal conductors, solutions of: Ba(OH)2, NaOH, Na2CO3, CuSO4, H2SO4, CH3COOH, NH3*H2O METHOD Place a drop of each solution and …

…phenolphthalein is transparent when meets acid when it changes red when meets base. The buffer solution could be created by a mixture of a weak acid and a bit of strong base. Through the brightness of the light bulbs, we can see that the electrical conductivity is higher for the stronger acid and stronger base and is lower for the weaker acid and weaker base and pure water, whose pH values are closer to seven.