Chemical Composition of Seawater

Test your understanding of the chemical composition of seawater, including major ions, minor ions, and dissolved gases.

15 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

Which ion is the most abundant in seawater?

  1. Chloride
  2. Sodium
  3. Magnesium
  4. Calcium
Question 2 Multiple Choice (Single Answer)

Which ion is the second most abundant in seawater?

  1. Sodium
  2. Magnesium
  3. Calcium
  4. Potassium
Question 3 Multiple Choice (Single Answer)

Which ion is the third most abundant in seawater?

  1. Magnesium
  2. Calcium
  3. Potassium
  4. Sulfate
Question 4 Multiple Choice (Single Answer)

Which ion is the fourth most abundant in seawater?

  1. Calcium
  2. Potassium
  3. Sulfate
  4. Bicarbonate
Question 5 Multiple Choice (Single Answer)

Which ion is the fifth most abundant in seawater?

  1. Potassium
  2. Sulfate
  3. Bicarbonate
  4. Bromide
Question 6 Multiple Choice (Single Answer)

Which gas is the most abundant in seawater?

  1. Nitrogen
  2. Oxygen
  3. Carbon Dioxide
  4. Argon
Question 7 Multiple Choice (Single Answer)

Which gas is the second most abundant in seawater?

  1. Oxygen
  2. Carbon Dioxide
  3. Argon
  4. Helium
Question 8 Multiple Choice (Single Answer)

Which gas is the third most abundant in seawater?

  1. Carbon Dioxide
  2. Argon
  3. Helium
  4. Methane
Question 9 Multiple Choice (Single Answer)

Which gas is the fourth most abundant in seawater?

  1. Argon
  2. Helium
  3. Methane
  4. Hydrogen Sulfide
Question 10 Multiple Choice (Single Answer)

Which gas is the fifth most abundant in seawater?

  1. Helium
  2. Methane
  3. Hydrogen Sulfide
  4. Nitrous Oxide
Question 11 Multiple Choice (Single Answer)

What is the average salinity of seawater?

  1. 35 parts per thousand
  2. 30 parts per thousand
  3. 40 parts per thousand
  4. 45 parts per thousand
Question 12 Multiple Choice (Single Answer)

What is the pH of seawater?

  1. 8.1
  2. 7.0
  3. 6.0
  4. 5.0
Question 13 Multiple Choice (Single Answer)

What is the primary source of dissolved solids in seawater?

  1. Weathering of rocks
  2. Volcanic eruptions
  3. Hydrothermal vents
  4. All of the above
Question 14 Multiple Choice (Single Answer)

How does the chemical composition of seawater vary with depth?

  1. It remains constant
  2. It becomes more concentrated
  3. It becomes less concentrated
  4. It varies depending on the location
Question 15 Multiple Choice (Single Answer)

How does the chemical composition of seawater vary with latitude?

  1. It remains constant
  2. It becomes more concentrated near the equator
  3. It becomes less concentrated near the equator
  4. It varies depending on the location