Table 1.

Determination of Hg²⁺ ions in water samples.

Sample	Hg2+ Ion (M) Spiked	Hg2+ Ion (M) Detected	Recovery (%)
Tap Water	10	10.09	100.9
	15	14.69	97.93
Drinking Water	10	10.1	101.0
	15	14.58	97.2
Groundwater	10	9.71	97.1
	15	14.71	98.07

FH@Ni(MOF) was used for the detection of Hg²⁺ by the standard addition method. All the water samples were filtered three times through a 0.2 mm membrane filter.