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Biochemistry Notes. Elements and Atoms. Matter is anything that has mass and takes up space. Atoms are the basic building blocks of all matter. Elements are basic substances that cannot be broken down into other substances.
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Elements and Atoms • Matter is anything that has mass and takes up space. • Atoms are the basic building blocks of all matter. • Elements are basic substances that cannot be broken down into other substances. • Molecules are formed by the joining of atoms of two or more elements.(smallest combination that cannot be divided without changing its chemical and physical properties) • Compoundsare composed of atoms of different elements chemically combined.
Atoms • The center of an atom is called the nucleus. • Consists of three subatomic particles called: • Protons: positive charge • Neutrons: neutral/no charge • Electrons: negative charge • 1st level can hold 2 electrons • 2nd level can hold 8 electrons • 3rd level can hold 8 electrons
Atomic Number: Protons Symbol Element Atomic Mass Number: Protons + Neutrons Periodic Table 12 Mg Magnesium 24.305 (Nucleus) QUESTION: What part of the atom gives the atom its mass??
Protons Protons + Neutrons Periodic Table 12 Mg Magnesium 24.305 Protons = Electrons In a neutral atom
Periodic Table 12 Mg Magnesium 24.305 Protons = Electrons = Neutrons = 12 12 24-12 = 12
Bonding The sharing of electrons in order to become stable is called covalentbonding. (2 nonmetals)
Periodic Table H H O Water
Bonding + + - Water Covalent Bond
Bonding • The gaining or losing of electrons in order to become stable is called ionic bonding. ( a metal with a nonmetal) http://www.dac.neu.edu/physics/b.maheswaran/phy1121/data/ch09/anim/anim0904.htm
Bonding Sodium Chloride
Bonding + - Sodium Chloride Ionic Bond
Chemical Equations CH4 + 2O2 CO2 + 2H2O Reactants Products CO2 + H2O + LIGHT ENERGY C6H12O6 + O2 Equation for Photosynthesis 6 6 6
Inorganic Substances Not Containing Carbon • Acids: substances that forms hydrogen (H) hydrogen ions in water. pH of 0-7. • Bases: substance that forms hydroxide ions (OH) in water. pH scale of 7-14. • Salts: Inorganic substances that typically contain Chlorine. HCl NaOH NaCl H2SO4 MgCl2 KOH
Organic Substances Molecule that is found in living systems; contains carbon; usually in rings or long chains
Organic Substances • Carbohydrates: made up of simple sugars (saccharides)
Organic Carbohydrate Protein Lipid Nucleic Acid Inorganic Acid Base Salt