A chemical substance has the characteristics that it cannot be separated by physical methods. Seawater and milk can be separated by sedimentation, and air has different components depending on other aspects (such as elevation). Only ammonia is a substance. (thus it can have a formula: NH<span>3)</span>
Each year over 100,000 new organic compounds are produce
<h2>Answer:</h2>
The option B is correct option. Which is release of heat and/or light energy .
<h3>Explanation:</h3>
According to the definition of exothermic reaction :
<em>An exothermic reaction is a chemical reaction that releases energy by light or heat.</em>
From definition option B (release of heat and/or light energy) indicates that an exothermic reaction has taken place.
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I believe the correct answer among the choices listed above is option C. <span>Methane burns in oxygen to yield carbon dioxide and water. In chemical symbols, it is represented as:
</span><span>CH4 + 2O2--> CO2 + 2H2O</span>
