What I have been learning in Science Class

In Science class, I have been learning about the theory about atoms-what they are made of, their electronic configuration and so on. Atoms are interesting to learn about as they make everything up on earth. Even earth itself.

Firstly, we learnt about the anatomy of an atom. An atom is said to contain a dense nucleus of protons and neutrons surrounded by electrons in orbitals.

Only the electrons are involved in chemical reactions. Electrons are tiny particles that carry a negative charge. They move in orbits around the nucleus. There are rules to orbiting.

1. The electron shell closest to the nucleus can only have up to two electrons.

2. Subsequent shells can have up to eight electrons.

3. For any atom belonging to an element after calcium(Ca), the third shell onwards can hold up to eighteen electrons.

The protons are fixed. They carry a positive charge. Atoms of an element carry a specifically defined number of protons. The neutrons have no charge. They are said to be neutral.

In chemical bonding, electrons interact. There are two kinds of bonding, chemical and covalent. In chemical bonding, an atom loses its electrons to another atom so that they both reach a stable electronic configuration of 2 or 8. Then they can form a compound, like sodium chloride or magnesium oxide. More will be shown in the next post.