Structure of an Atom
Download as PPTX, PDF4 likes3,442 views
- Dalton's model proposed that all matter is made of tiny particles called atoms, all atoms of the same element are alike but different from other elements, and compounds form from atoms combining in fixed proportions. Thomson's model pictured the atom as a positively charged sphere with electrons embedded within it. Rutherford's model showed that the atom's positive charge and most of its mass are concentrated in a tiny, dense nucleus at the center with electrons orbiting outside. The parts of an atom include the nucleus containing protons and neutrons at its center, surrounded by electrons. Protons have a positive charge while neutrons have no charge. Electrons have a negative charge and much less mass than protons or neutrons.
Structure of an Atom
- 1. STRUCTURE OF AN ATOM BY IRA DEOKULE VIII J ROLL NO. 6
- 2. Developments in the model of atom
- 3. Dalton’s Model Also known as the billiard ball model • All matter is made up of tiny particles called atoms. • All atoms of a given element are a like, but are different from the atoms of any other element. • Compounds are formed when atoms of different elements combine in fixed proportions. • A chemical reaction involves a rearrangement of atoms, not a change in the atoms themselves.
- 4. Thomson’s Model Also known as the plum pudding or water melon model
- 5. Rutherford’s Model • The atom's electron cloud does not influence alpha particle scattering. • Much of an atom's charge (specifically, its positive charge) is concentrated in a relatively tiny volume at the nucleus. • The magnitude of this charge is proportional to (up to a charge number that can be approximately half of) the atom's atomic mass - the remaining mass is now known to be mostly attributed to neutrons. • This concentrated central mass and charge is responsible for deflecting both alpha and beta particles. • The mass of heavy atoms such as gold is mostly concentrated in the central charge region.
- 6. Parts of the atom
- 7. Nucleus • A model of the atomic nucleus showing it as a compact bundle of the two types of nucleons: protons and neutrons. • In simple diagrams they look like little balls stuck together but an actual nucleus cannot be explained like this but only by using quantum mechanics. • In a nucleus which occupies a certain energy level each nucleon can be said to occupy a range of locations.
- 8. Neutron • The neutron is a subatomic particle with no electric charge. • The nucleus consists of a number of protons and neutrons. • The mass of the neutron is slightly larger than that of proton. • In the nucleus, the protons and neutrons are bound together through nuclear force and neutrons are needed for the stability of the nuclei. • Even though it is not a chemical element it is included in the table of nuclides.
- 9. Protons • The proton is subatomic particle with a positive electric charge. • The nucleus consists of a number of protons and neutrons. • The mass of the proton is slightly larger than that of neutron. • The number of protons in the nucleus is referred to as it’s atomic number.
- 10. Electrons • The electron is a subatomic particle with a negative charge. • The mass of the electron is approximately 1/1836 that of proton. • An electron generates a magnetic field. • Electrons have many applications, including electronics, welding, cathode ray tubes, electron microscopes, radiation therapy, lasers, gaseous ionization detectors and particle accelerators etc.
- 11. Thank You