The five basic types of chemical reactions are combination, decomposition, single
replacement, double replacement, and combustion.
<span>The smallest unit of an element that retains all the characteristics of that element is called an A. atom.
Atoms consist of protons, electrons, and neutrons, but they are particles and don't have the characteristics of the element which is why D is incorrect. B and C are not the smallest units - atoms are smaller than them.
</span>
Answer:
A (H)
Explanation:
The key uptop shows all the red are non metal and "H: is pink
Si -Atomic number -14 -1s2 2s2 2p6 3s2 3p2 - 4 valence electrons
