Question

When baking soda is mixed with lemon juice bubbles are formed with the evolution of a gas.What type of change is it? Explain.

Answer 1

that is a chemical change 
more defined --- irreversible chemical change

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it is a chemical change because there is a change happening where new substances are produced at the same time old ones are getting changed .as there's a complete new change happening accompanying with new products and new properties it is a chemical change.

Answer 2

Explanation:

When baking soda is mixed up with lemon juice, bubbles are formed with evolution of carbon dioxide gas. It is an irreversible chemical change.