A food item that is left out of the refrigerator turns brown and forms bubbles and gas. What are the signs that this is a chemical reaction? Check all that apply.Heat is produced.Heat is absorbed.Bubbles appear.A precipitate forms.The color changes.

Bubbles and gas indicate that a gas is being produced, which is a sign of a chemical reaction. The food turning brown is a color change, another sign of a chemical reaction. The question gives no evidence that heat is produced or absorbed, or that a precipitate forms.

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