The heat that comes from burning wood comes from chemical reactions. You could also argue that heat energy originally comes from sunlight. How is this true?

Well, heat energy comes from sunlight in a process called radiation. Burning wood is chemical because the wood is now ash and not in the state it was. Hope this helps. :)

Explanation:

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Explanation:

Salt makes ice to melt faster than it usual. Sugar is another substance that influences the melting time of ice.

If i have a sample of pure ice and another sample of ice treated with sugar. I have to maintain the both initially at 0 degrees temperature and have a stop clock to measure the melting time.

I will ultimately notice that the sample of ice treated with sugar will melt faster than the pure sample of ice due to the presence of an impurity.