18. In some chemical reactions, such as
photosynthesis, several different compounds
take part in the reaction. How do you think that
atoms present at the end of this kind of reaction
compare to the atoms present at the beginning
of the reaction? Explain.

Explanation:

Just like a chemical reaction, the atoms do not change and the number of atoms on the reactant side of the reaction is equal to that on the product side of the equation. (See attached diagram)

This is why we balance chemical equations in observance to the laws of thermodynamic on the conservation of matter and energy. In chemical reaction conservation of matter is observed. The atoms involved in the reactions are merely re-arranged and become part of new chemical bonds.

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.