Most surface water is low in minerals, gases, and ________.

Most surface water is low in minerals, gases, and ________.

• A. dissolved solids
• B. dissolved oxygen
• C. minerals
• D. salts

Answer: (A)

The main idea is understanding how much dissolved material is in surface water. Surface water tends to be relatively dilute because it hasn't had the extensive contact with minerals in rocks that groundwater has. The total amount of inorganic material dissolved in water is described by the term dissolved solids (also known as total dissolved solids, TDS). This concept captures all minerals and salts dissolved in the water, which is why surface water is typically low in dissolved solids. Dissolved oxygen is a gas and is usually present in surface water due to exchange with the air and photosynthesis, so it’s not typically described as being low. Minerals and salts are components of dissolved solids, so mentioning dissolved solids covers the overall dissolved mineral content more accurately.

The main idea is understanding how much dissolved material is in surface water. Surface water tends to be relatively dilute because it hasn't had the extensive contact with minerals in rocks that groundwater has. The total amount of inorganic material dissolved in water is described by the term dissolved solids (also known as total dissolved solids, TDS). This concept captures all minerals and salts dissolved in the water, which is why surface water is typically low in dissolved solids. Dissolved oxygen is a gas and is usually present in surface water due to exchange with the air and photosynthesis, so it’s not typically described as being low. Minerals and salts are components of dissolved solids, so mentioning dissolved solids covers the overall dissolved mineral content more accurately.