If you could measure the mass of the substances inside the cup before and after the reaction, you would see that the mass decreased over a course of the reaction. explain the difference.

In a popular classroom demonstration, solid sodium is added to liquid water and reacts to produce hydrogen gas and aqueous sodium hydroxide. part a write a balanced chemical equation for this reaction. express your answer as a chemical equation. identify all of the phases in your answer.

If you add 10ml of hot water to 10ml of cold water and the change in tempature 8°c calculate how much energy is gained by the cold water

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