Why does shampoo bubble up WAY more the second time you apply it?

Question

When I’m in the shower, sometimes I’ll notice my hair is particularly greasy and once I’ve rinsed off the first round of shampoo, I’ll apply a second round. And no matter how small of an amount I apply the second time around, it turns into a baby bubble bath commercial with oodles of suds and bubbles and foam all over the place?

Is it because the first lot got used up on a larger bulk of grease and the second amount doesn’t and so it can bubble up more?

In: Chemistry

Answer 1

Basically the first time most of it is stuck to dirt and oil, so it’s not available to make bubbles. The second time it’s a lot less, so more bubbles!