Acid Erosion
Acid erosion is what happens when an acid slowly eats away at a solid material, like vinegar dissolving an eggshell.
Think of it this way
Acid erosion works like vinegar slowly dissolving an eggshell. Drop a raw egg in a cup of vinegar and wait two days. The hard shell disappears, leaving only a soft, rubbery egg. The acid in the vinegar breaks apart the solid shell bit by bit, the same way acids in nature wear away rocks and metals over time.
Explaining acid erosion by grade level
When you put an egg in vinegar, tiny bubbles show up on the shell. The vinegar is breaking the hard shell apart, bit by bit. After a few days, the shell is gone and the egg feels rubbery. The acid in the vinegar wore the shell away, the same way acids can wear away rocks and teeth over time.