The safe permissible limits of sulphate and chloride in domestic water supplies, respectively, are

A400 mg/l and 1000 mg/l ✓ Correct

B200 mg/l and 800 mg/l

C800 mg/l and 400 mg/l

D500 mg/l and 500 mg/l

Correct answer: (A) 400 mg/l and 1000 mg/l

Explanation

The safe permissible limits are 400 mg per litre for sulphate and 1000 mg per litre for chloride in domestic water.

The pairing of 200 and 800 understates both permissible ceilings.

The pairing of 800 and 400 reverses and misstates the two figures.

The pairing of 500 and 500 gives an equal, incorrect value to both.

Sulphate above its limit can cause a laxative effect and a bitter taste.

Excess chloride imparts a salty taste and can corrode pipes.

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