Carbs!! (or carbohydrates)
They are kind of opposite processes. Chemical synthesis is execution of chemical reactions to make products. Like you take two substances, you put them together, they react and you have new a substance. For example.

here Sodium and Chlorine react to make a new substance which is Sodium Chloride.
Chemical decomposition is process of seperating a substance to different substances. There is a substance by a reaction this substance becomes two substances, Like : XY -> X+Y For example :
<h2>Question</h2>
How does glue, borax, and water turn into slime, scientifically?
<h2>Answer</h2>
- It is the matter of time and Weather
Answer:
D
Explanation:
The indivisibility of an atom was proved wrong an atom can be further subdivided into protons, neutrons and electrons. However an atom is the smallest particle that takes part in chemical reactions......
hope i helped
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