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.

chemical weathering

explanation:

hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

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