Unique Nature of pure water (section1)
What are the two elements that make up water?
hydrogen and oxygen
What is the main substance dissolved in seawater?
Salt
What is the average pH of seawater?
Around 8
What human activity increases CO, in the air?
Burning fossil fuels
What process in plants uses CO2?
Photosynthesis
What is the shape of a water molecule?
Bent (V-shaped)
What happens to seawater when it gets warmer?
it becomes less dense
What does pH measure?
How acidic or basic a solution is
What weak acid forms when CO, dissolves in seawater?
Carbonic acid
What process in animals releases CO2?
Respiration
What makes water molecules stick together?
Hydrogen bonding
What happens to salinity when lots of rain falls into the ocean?
Salinity decreases
What gas dissolves in seawater and helps form carbonic acid?
Carbon dioxide
How does ocean acidification harm coral reefs?
It makes it harder for coral to build skeletons
How do oceans help store carbon?
They absorb CO, from the atmosphere
Why is water called the "universal solvent"?
Because it can dissolve many different substances
Why does salty water freeze at a lower temperature than fresh water?
The salt interferes with ice formation
What happens if seawater's pH goes down?
It becomes more acidic
Why does acidification lower carbonate ion levels?
extra H+ ions
What happens to carbon from dead marine organisms?
It sinks and becomes part of ocean sediments
Why does water have a high surface tension?
Hydrogen bonds pull water molecules tightly together at the surface
How does temperature and salinity together affect seawater density?
Colder, saltier water is denser than warm, less salty water
Why is it important for ocean pH to stay balanced?
To protect marine life and chemical stability in the ocean
What could happen to food chains if acidification continues?
Shell-building animals could decline, hurting larger species that depend on them
How are the atmosphere, oceans, and living things connected in the carbon cycle?
Carbon moves between them through photosynthesis, respiration, and decomposition