 |
| Atom |
The nucleus is surrounded by electrons, which have a negative charge. The positively charged protons and negatively charged electrons attract each other. Each atom is held together by this force of attraction.
Splitting of atoms
Most atoms can be arranged into different groups, to make different substances. The atoms of a few metals can be changed, or split, to make new, different atoms. The nucleus of an atom of metal called uranium can be split into two.This is called nuclear fission. The word “fission” means breaking apart.
When the nucleus of a uranium atom is split, some of its neutrons escape. These neutrons crash into other uranium atoms, causing them to split. As the nucleus of the atom is split, it releases huge amounts of heat. In a nuclear power station, this heat energy is used to produce electricity.
Fusing atoms
The nuclei of the atoms of the gas hydrogen cannot be split, but they can be squeezed together.This process is called nuclear fusion. The word “fusion” means joining together.
A type of hydrogen gas called deuterium is heated to extremely high temperatures. The deuterium atoms crash into each other and form heavier elements. This process releases large amounts of energy. Scientists are trying to find a way of using nuclear fusion in power stations because it will be one of the cheapest and cleanest ways of producing electricity.
The sun’s energy comes from the nuclear fusion of hydrogen atoms. The hydrogen atoms in the sun continually crash into each other and fuse, making larger atoms of helium gas.
An atom is made up of three different types of particles—protons, neutrons, and electrons. The protons and neutrons are crowded into the nucleus near the center of the atom. The electrons go around the nucleus at fantastic speeds.
The photograph shows the mushroom-shaped cloud that rises up into the air following a nuclear explosion.
Social Plugin