Consider the following statements about the salinity of water bodies: 1. The average salinity of the oceans is approximately 10 parts per thousand. 2. The Dead Sea has a salinity of 340 grams per litre. 3. River water contains small amounts of dissolved salts. Which of the statements given above is/are correct?

Correct Option The correct option is (c) 2 and 3 only. Explanation Salinity is the amount of salt in grams present in 1,000 grams of water. It is usually expressed as parts per thousand (ppt). The salinity of water bodies varies significantly depending on evaporation, precipitation, and the influx of fresh water. Statement-wise Analysis - Statement 1 is Incorrect. The average salinity of the oceans is approximately 35 parts per thousand (35 ppt), not 10 parts per thousand. While salinity can vary slightly between different oceans (typically ranging from 33 to 37 ppt), 10 ppt is characteristic of brackish water, not open ocean water. - Statement 2 is Correct. The Dead Sea in Israel is a hypersaline lake with a salinity of approximately 340 grams per litre (340 ppt). This extremely high salt concentration increases the density of the water, allowing swimmers to float easily. - Statement 3 is Correct. River water contains small amounts of dissolved salts. These salts are derived from the weathering of rocks and soil erosion as water flows over land. Although the concentration is low (usually less than 0.5 ppt, classifying it as fresh water), it is not devoid of salts. Key Takeaway: The average salinity of the world's oceans is 35 parts per thousand. Hypersaline bodies like the Dead Sea have much higher salinity (approx. 340 ppt), while fresh water contains trace amounts of dissolved salts.

NCERT Class 7 Geography — Chapter 1: Water

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Consider the following statements about the salinity of water bodies:

The average salinity of the oceans is approximately 10 parts per thousand.
The Dead Sea has a salinity of 340 grams per litre.
River water contains small amounts of dissolved salts.

Which of the statements given above is/are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

Correct Option

The correct option is (c) 2 and 3 only.

Explanation

Salinity is the amount of salt in grams present in 1,000 grams of water. It is usually expressed as parts per thousand (ppt). The salinity of water bodies varies significantly depending on evaporation, precipitation, and the influx of fresh water.

Statement-wise Analysis

Statement 1 is Incorrect. The average salinity of the oceans is approximately 35 parts per thousand (35 ppt), not 10 parts per thousand. While salinity can vary slightly between different oceans (typically ranging from 33 to 37 ppt), 10 ppt is characteristic of brackish water, not open ocean water.
Statement 2 is Correct. The Dead Sea in Israel is a hypersaline lake with a salinity of approximately 340 grams per litre (340 ppt). This extremely high salt concentration increases the density of the water, allowing swimmers to float easily.
Statement 3 is Correct. River water contains small amounts of dissolved salts. These salts are derived from the weathering of rocks and soil erosion as water flows over land. Although the concentration is low (usually less than 0.5 ppt, classifying it as fresh water), it is not devoid of salts.

Key Takeaway: The average salinity of the world's oceans is 35 parts per thousand. Hypersaline bodies like the Dead Sea have much higher salinity (approx. 340 ppt), while fresh water contains trace amounts of dissolved salts.

Your note

More from Chapter 1: Water

The process by which water continually changes its form and circulates between oceans, atmosphere, and land is best described by which of the following terms?

easy

With reference to the distribution of water on Earth, consider the following statements: 1. Groundwater has a larger volume than inland seas and salt lakes. 2. Inland seas and salt lakes contain more water than the atmosphere. 3. The volume of water in the atmosphere is greater than that in rivers. 4. Rivers hold the least volume of water among these four sources. Which of the statements given above are correct?

hard

Consider the following statements regarding the Earth's water: 1. The water cycle ensures that the water existing today is entirely different from the water that existed centuries ago. 2. The major sources of fresh water include rivers, ponds, springs, and glaciers. 3. The amount of water in the atmosphere is higher than that in fresh water lakes. Which of the statements given above is/are correct?

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In the context of water distribution, which of the following accounts for the largest percentage of fresh water on Earth?

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Consider the following statements regarding salinity: 1. Salinity is defined as the amount of salt in grams present in 1000 grams of water. 2. The average salinity of the oceans is generally 45 parts per thousand. 3. Most of the salt in the ocean is sodium chloride. Which of the statements given above is/are correct?

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Correct Option

The correct option is (c) 2 and 3 only.

Explanation

Statement-wise Analysis

Statement 1 is Incorrect. The average salinity of the oceans is approximately 35 parts per thousand (35 ppt), not 10 parts per thousand. While salinity can vary slightly between different oceans (typically ranging from 33 to 37 ppt), 10 ppt is characteristic of brackish water, not open ocean water.
Statement 2 is Correct. The Dead Sea in Israel is a hypersaline lake with a salinity of approximately 340 grams per litre (340 ppt). This extremely high salt concentration increases the density of the water, allowing swimmers to float easily.
Statement 3 is Correct. River water contains small amounts of dissolved salts. These salts are derived from the weathering of rocks and soil erosion as water flows over land. Although the concentration is low (usually less than 0.5 ppt, classifying it as fresh water), it is not devoid of salts.