Answer:
the third one
Explanation:
physical change is only on looks
Answer:
O silicon (Si)
Explanation:
-Valence electrons are electrons of the outermost shell which can participate in chemical bonding. ... -As in silicon, four electrons are present in the outermost shell, so silicon has Four valence electrons.
1. Calcium carbonate minerals are the building blocks for the skeletons and shells of mini marine organisms. It is important to ocean creatures because they make their shells out of this material. Examples of animal products that are primarily of calcium carbonate include seashells, egg shells, pearls, and notably coral