The Chemistry of life
The nature of matter Atoms: basic unit of matter, 3 elements: - Proton: positively charged particle, located at the center of the atom in the nucleus. The Hydrogen atom isunique in that it only has a single Proton and no Neutron in its nucleus. - Neutron: doesn't have any charge. The number of neutrons affects the mass and the radioactivity of the atom. - Electron:negatively charged particle that spins around the outside of the nucleus. They are attracted to it by the positive charge of protons. The area where electron can be found is called “Electron cloud”. If thereare the same number of electrons and neutrons in an atom, then the atom is said to have a neutral charge.. Electrons are arranged in energy levels, each level has a different distance from thenucleus. The closest to the nucleus, the lower is the energy level. Each energy level can hold only a certain number of electrons: 1st-2/ 2nd-8/ beyond 2nd level up to 32. However electrons can change fromone level to another, if they gain or lose energy. These elements can be shared of transferred between atoms, but only those that are on the outer level. Think of this as when you open the fridge toget a bottle of water, the easiest one to grab is the one on the edge; the others at the back represent an extra effort. Chemical compounds: Substance formed by the chemical combination of two or moreelements in definite proportions. Chemical element: pure substance that consists entirely of one type of atom (ie: CarbonC; Hydrogen-H). These are represented on the Periodic table of elements, by aletter (or 2), it’s atomic number (number of protons). Some elements however have the same atomic number, but different number of neutrons in their nucleus, these are called: Isotopes. Most elementshave 2 or more isotopes IE: Carbon has 3 isotopes C12 / C13 / C14 Hydrogen has 3 isotopes H1 (protium) / H2(deuterium)/ H3(tritium)
Electronegativity: The higher the electronegativity, the fewer...
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