Friday, March 4, 2011

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.

Welcome and Introduction


Welcome to this blog, I am Timothy Leong. As of 2011 I am in 2O3, Hwa Chong Institution. This is a Science E-portfolio, a platform whereby I can post matters that are related to Science, e.g lessons, new advancements in technology, etc. This is mostly a blog of information-bites, which are (small)but interesting posts.

Welcome again.

Technology- the all-new stretchy solar cells

Stretchy-solar-cell-600x400

This is a stretchable solar cell. It can withstand stretching up to 30% when pulled from both ends. This could lead to robotic skin that are durable and can pick up sensory details from the environment.The device's electrode is made from a unique liquid metal called eutectic gallium-indium, which conforms to a surface as it lengthens and relaxes. "Eutectic" refers to a mix of elements or compound that remains liquid at lower temperature than either of its components does alone.

This is good as solar cells eliminate the need for a battery cell or charging. Also, its stretchability is good as it can withstand damage from wear and tear like scratching, grazing... this is not commercially available yet, but I think it will be very useful when it comes out. I think it can be used for:

- Robots in space
- Shopping centre walls
- Cars