Table 1.

Mean and standard deviation of pH values of two buffer solutions measured with the new electronic device

	0.7 M acetate buffer pH = 5.5		0.15 M phosphate buffer pH = 6.5
	Mean	Standard deviation	Mean	Standard deviation
Intra-day (n = 5)	5.42	0.04	6.50	0.00
Inter-day (n = 5)	5.46	0.05	6.50	0.00