Basic Chemistry Chemistry Chemistry is the science of
Basic Chemistry
Chemistry: • Chemistry is the science of matter. – Scientists study chemicals, their properties, and REACTIONS (rxn). • BIOCHEMISTRY is the chemistry of living things.
Water: • most chemical rxns occur only in water (universal solvent) • 90% or more of cells is H 2 O • essential to life • Solutions are made up of the – Solute: – Solvent:
Elements • most simple substance of matter • cannot be broken down • ex. Fe. O, Mg, Na
Valence Electrons: • outermost electrons • (carry negative charge) • responsible for bonding • goal: to have a full valence energy level
Boxes on the Periodic Table • Each box on the PT contains the following information: – Atomic number = – Atomic Mass = – Atomic Symbol = – # of protons = – #of neutrons = – # of electrons = 6 C 12. 001
Compound • Chemically bonding of 2 or more elements formed by: 1. 2. 3. 4. Ionic Bonds: Covalent Bonds Polar Bonds Hydrogen Bonds
Ionic Bond: –transfer of valence e–Forms between a metal and a nonmetal –Ex. KI Potassium Iodide
Covalent bond: –Forms between 2 nonmetals –Ex. CO = Carbon Monoxide –Equal Sharing of Valence electrons
Polar Bonds • between covalent and ionic bonds • unequal sharing of the valence electrons • have slightly positive and slightly negative ends • Ex. Water!!
Adhesion and Cohesion • Water is attracted to other water. – This is called cohesion. • Water can also be attracted to other materials. – This is called adhesion.
Surface Tension • the cohesion of water molecules at the surface of a body of water
Capillary Action • Capillary action however, is related to the adhesive properties of water. • water molecules are attracted to the straw molecules.
Hydrogen Bonds : –Weaker bonds than ionic and covalent –Allow for large biological molecules • Ex. Proteins • DNA –Bonds water molecules together
Acid and Bases: • Are ionized • Can conduct electrical current • Located throughout the body – Ex. Mouth, stomach
Acid : Acids: • Have extra H+ ions • Have a sour taste • Have a low p. H (between 1 – 5)
Bases: • Have OH- ions • Have a slippery feel • Have a high p. H (b/w 8 -12)
p. H Scale: • Based on the # of H ion present
Buffers: • keep its p. H constant • resist changes in p. H when acids or bases are added to them. • In the body proteins act as a buffer, ex. Blood
Neutralization: • Combing an Acids with a base • results is neither an acid or a base. • H+ form the acid and the OH- form the base combine to form water • Ex. HCl + Na. OH Na. Cl +H 2 O acid + base salt + water
Acid , Base Indicators: • Phenolphthalein (base only) • p. H paper (both) • Universal Indicator Solution (Both) • Litmus paper (either) – Red – Blue
Litmus paper:
p. H paper:
Universal Indicator Solution:
Phenolphthalein: Clear in the presence of an acid Pink in a base
Inorganic chemistry: • compound usually does not contain carbon or hydrogen
Organic Chemistry: • the compounds usually found in Living or once living things • contains carbon and hydrogen • most common elements in living things are: • C, H, O, N, P • Carbon is often referred to as the element of LIFE ***CHANGES ON THIS SLIDE***
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