In a filtration plant, water is filtered using layers of
(a) sand and clay
(b) clay and fine gravel
(c) sand and fine gravel
(d) sand, fine gravel and medium gravel

AcademicChemistryNCERTClass 7

Correct Answer: (d) sand, fine gravel and medium gravel

Explanation: In wastewater treatment, waste¬water is allowed to enter a grit and sand removal tank, where the speed of wastewater is reduced in order to allow sand, grit and pebbles to settle down.

Updated on 10-Oct-2022 13:22:17