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Mission 9 of 16

Ocean Chemistry & Acidification

📋 What it is

Seawater is salty and slightly basic; absorbing extra CO₂ makes it more acidic, harming shell-builders.

🗣️ Coach says

Seawater is a chemical soup — mostly salt, plus dissolved gases and minerals. The ocean absorbs huge amounts of CO₂ from the air, which is helpful for climate but has a cost: it makes the water more ACIDIC. That acidification makes it harder for corals, shellfish and plankton to build their shells.

🧠 Memory hook

Seawater = salty chemistry. It absorbs CO₂ (helps climate) BUT gets more acidic → harder for shells to form.

😂 Giggle

Why don't anglerfish ever need flashlights?
They come with their own built-in lure lighting!

😲 Whoa!

The ocean has absorbed roughly a quarter of all the CO₂ humans have ever released — quietly slowing climate change, but paying for it by turning more acidic.

✅ Quick check: How does the ocean absorbing extra CO₂ harm sea creatures?

Say your answer out loud first — then reveal.

🧪 Try it! (2 minutes)

Recall that a shell is like chalk — acid dissolves chalk, which is why acidifying water hurts shells.

⭐ Do the round to earn your star →
🤸 Brain break: Shell-check: cup your hands like a shell, then mime it slowly weakening in acid.