What is the salinity of the Dead Sea (per litre of water)?

Correct — A. School geography fixes the Dead Sea's salinity at 340 grams per litre of water — the figure NCERT's Class 7 chapter on water prints.

Set it against an ocean average of about 35 grams per litre and the scale is clear: roughly ten times as salty as seawater.

That is why a swimmer floats in it without effort — the dissolved salt makes the water dense — and why almost nothing lives in it. Option (a) reproduces the figure.

Why the others are wrong

• (b)
  390 grams — 390 g/l overshoots. The lake's brine does concentrate further as its level falls, but the value examinable here is the textbook one, 340.
• (c)
  440 grams — 440 g/l is the largest overshoot on offer — a hundred grams above the quoted figure, when Dead Sea brine is already close to saturation at 340.
• (d)
  240 grams — 240 g/l undershoots. It would still be extraordinarily saline beside seawater, which is what makes it survive a quick check, but the quoted value is 340.

Salinity is the mass of dissolved salts in a given quantity of water, written in grams per litre or in parts per thousand. Ocean water averages about 35 g/l.

Enclosed basins in hot, dry regions run far above that. The Dead Sea has no outlet: water arrives by the Jordan and leaves only by evaporation, so the salts stay behind and accumulate.

That mechanism — inland drainage plus high evaporation — is what the question is really about, and it is the part that transfers to other salt lakes.

Key facts

• The salinity of the Dead Sea is quoted as 340 grams per litre of water.
• Average ocean salinity is about 35 grams per litre.
• The Dead Sea lies between Israel and Jordan and has no outlet, so evaporation concentrates its salts.
• The high density of Dead Sea water is why swimmers float in it easily.

Common traps

• Mixing grams per litre with parts per thousand when comparing the Dead Sea against ocean water.
• Reasoning from "about ten times seawater" alone. 340, 390 and 440 g/l are all roughly ten times the ocean average, so that comparison cannot separate them — only the exact figure can.

No directly related past PYQ was found.