Since we know that , we can conclude that the gas produced when mixing bath bombs in water could not be baking soda, citric acid, or water.

Sodium bicarbonate.

Explanation:

The gas produced during the mixing of bath bombs in water is Sodium bicarbonate. If the reaction is with citric acid then Sodium citrate can be produced. They are weak acid with bicarbonate base. These bath bombs can be a mixture of wet and dry substances and any shape can be mold.

we need the questions , i may then you.

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.