Chemistry of Seawater Quiz

Front

Composition of seawater is unaffected by marine organisms.

Back

False

Answer explanation

The statement is false because marine organisms, such as phytoplankton and corals, influence the composition of seawater by contributing organic matter and altering nutrient levels through their biological processes.

Front

Helium is the most prevalent gas in the ocean.

Back

False

Answer explanation

The statement is false because nitrogen is the most prevalent gas in the ocean, not helium. Helium is present in much smaller quantities.

Front

Cohesion is the bonding of water molecules to each other.

Back

True

Answer explanation

The statement is true. Cohesion refers to the attraction between water molecules, which allows them to bond with each other. This property is crucial for many of water's unique characteristics.

Front

Water is the universal solvent.

Back

True

Answer explanation

The statement is true because water is known as the universal solvent due to its ability to dissolve more substances than any other liquid, making it essential for various biological and chemical processes.

Front

Air is denser than water.

Back

False

Answer explanation

The statement is false because air is less dense than water. Water has a density of about 1 g/cm³, while air at sea level has a density of approximately 0.0013 g/cm³, making air significantly less dense.

Front

Saltwater evaporates more quickly than freshwater.

Back

True

Answer explanation

True. Saltwater contains dissolved salts, which lower its vapor pressure compared to freshwater. This means that under the same conditions, saltwater evaporates more quickly than freshwater.

Front

Hydrogen bonds involve sharing electrons in compounds.

Back

False

Answer explanation

The statement is false because hydrogen bonds are not about sharing electrons; they are weak attractions between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom.

Front

Cohesion allows light organisms to walk on water's surface.

Back

True

Answer explanation

The statement is true. Cohesion, a property of water, creates surface tension that allows very light organisms, like water striders, to walk on the water's surface without sinking.

Front

Particulate matter in the ocean dissolves.

Back

True

Answer explanation

The statement is true because particulate matter in the ocean can dissolve in water, contributing to the overall chemical composition of seawater.

Front

Hydrogen bonds are weak and can easily break apart.

Back

True

Answer explanation

The statement is true. Hydrogen bonds are indeed weak interactions that can easily break apart, allowing for flexibility in molecular structures, such as in water and biological molecules.