Three ocean Water resource

Answer 1

What is your question?

Answer 2

why do bubbles released indicates that a chemical change has taken place

Answer 3

First, if you have a question, it is much better to put it in as a separate post in <Post a New Question> rather than attaching it to a previous question, where it is more likely to be overlooked.

Bubbles indicate that some sort of gas is being generated in the solution.

I hope this helps. Thanks for asking.