Weathering releases dissolved material from rocks, and rivers carry some of it toward the sea. Seafloor processes also supply substances. Salt is removed through biological and geological processes too. The ocean is not simply becoming saltier forever; sources, sinks and the water cycle interact over long periods.
Water and oceans · Discover & try
Why does evaporation leave the ocean’s salt behind?
Reading level 2 of 5 · DevelopingChange
Word help
Salinity
The concentration of dissolved salts in water.
Dilution
A reduction in concentration when more solvent is added.
Dissolved
Mixed into a liquid at the molecular or ionic scale.
Watch · Try · Explain
See how it works
The interactive activity is loading.
Ideal well-mixed basin using grams per litre; no crystallization, overflow or full ocean chemistry.
What to look for
- Keep salt mass fixed while water changes.
- Compare evaporation with fresh-water addition.
- Read grams per litre separately from total grams.
Explain what you noticed
A new covered bowl contains 20 grams of dissolved salt in 2 litres of water. It gains 2 litres of fresh water without losing salt. What happens?
Keep this idea: Evaporation removes water while leaving most dissolved salt; rain adds fresh water and dilutes it.
Follow the sources
Source material checked 2026-10-28. Explanations and activities by Nepedia. Source links do not imply endorsement.
Keep following the idea
Next discovery →