Chemistry of Ocean Water

Which gas is decreasing the ocean's pH?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Water Vapor

Tags

NGSS.HS-ESS2-6

NGSS.HS-LS2-5

Sodium ions and chloride ions account for about ____________ of ions in seawater.

• 55%

• 65%

• 75%

• 85%

Tags

NGSS.MS-PS1-1

Chloride ions make up 55.03% of the amount of salt present in the ocean. This is an example of:

• Theory of evolution by natural selection

• Laws of motion

• Rule of constant proportions

• Cell theory

Carbon dioxide diffuses into the ocean and combines with water (H₂O) to form carbonic acid (H₂CO₃). This ultimately breaks down and releases _________________________, causing the water to become more acidic.

• sodium chloride

• calcium carbonate

• hydrogen ions

• chlorophyll

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Water molecules are held together by which type of bond?

• Ionic

• Non-polar covalent

• Hydrogen

• Polar covalent

What are the attractions between water molecules called?

• Covalent bonds

• Ionic bonds

• Polar bonds

• Hydrogen bonds

What is the term for the amount of dissolved salts in a sample of ocean water?

• Salt

• Salty water

• Salinity

• Calcium

Select two reasons why salinity can increase.

• Evaporation occurs, causing water to change into water vapor and leaving salt behind.

• Freshwater is added to the ocean at the mouths of large rivers.

• Freshwater is added by rain, snow, and melting ice.

• Surface water freezes into ice, leaving salt behind.

Select two reasons as to why salinity can decrease.

• Evaporation occurs because water changes into water vapor, leaving salt behind.

• Freshwater is added to the ocean at the mouths of large rivers.

• Freshwater is added by rain, snow, and melting ice.

• Surface water freezes into ice, leaving salt behind.

How does salt affect ocean water?

• It lowers the freezing point.

• It raises the freezing point.

• It increases the density, giving ocean water greater buoyancy.

• It decreases the density, giving ocean water lower buoyancy.