basic chemistry chapter 2. matter & energy matter anything that occupies space and can be...
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MATTER & ENERGY• Matter
• Anything that occupies space and can be weighed
• Chemistry examines the nature of matter
• Energy
• No mass
• Ability to do work
• Matter is the substance that is moved by energy
Matter
• Building blocks: solid, liquid, gas
• Physical change –nature of substance is unchanged
• Chemical change –nature of substance is changed
ENERGY• Forms:
• Chemical -stored within bonds, released as heat
• Electrical -movement of charged partials (e-)
• Mechanical -direct movement of matter
• Radiant -electromagnetic waves
• Energy is converted from one form to another, any not used is released as heat.
COMPOSITION OF MATTER
• Elements
• Atoms
• Protons (p+) –positive charge
• Neutrons(n0) –neutral or no charge
• Electrons (e-) –negative charge
• Opposites attract!
http://www.chemicalelements.com/
ATOMS
• Orbital Model –electron cloud
• Atomic number –number of protons
• Atomic mass –sum of all protons and neutrons
• Isotopes –vary in number of neutrons
• Radioisotopes –radioactivity, heavy isotopes
CHEMICAL BONDS & REACTIONS
• Molecules, Compounds, Reactions, OH MY!
• Molecules =same
• Compounds =different
• Reactions =associations or dissociations of atoms
• Bonds form between molecules and compounds
• Energy relationships
CHEMICAL BONDS
• Bonds are energy relationships
• Opposites attract while “like” or same repels
• Role of electrons
• Occupy fixed regions called electron shells or energy levels
• Valence shell electrons participate in bonds
ENERGY LEVELS
• Valence Shells (energy levels)
• Outer shell
• If fewer than 8 electrons will try to: share, gain, lose
CHEMICAL BONDS• Ionic –one atom gains electron and second loses
• Covalent –electrons are shared between atoms
• Hydrogen –form bridge between two electrically negative atoms
CHEMICAL REACTIONS
• Synthesis –larger molecule formed
• Decomposition –larger molecule is degraded
• Exchange –synthesis and decomposition; switch
BIOCHEMISTRY
• Inorganic compounds do not contain carbon atoms
• Water, salts (electrolytes), acids and bases
• Organic compounds contain carbon atoms
• Carbohydrates, lipids, proteins and nucleic acids
INORGANIC COMPOUNDS
• Water –thermoregulatory, universal solvent, reactivity, cushioning, lubrication
• Salts –cations other than H+, electrolytes
• Acids –H+, proton donors
• Bases –OH-, proton acceptors
• pH –concentration of acid; [protons]
pH 7 =1 x 10-7 pH2 =1 x 10-2 pH12 =1 x 10-12
ORGANIC COMPOUNDS
• Large, complex molecules
• Functional groups are reactive parts
• Monomers combine to form polymers
• Carbohydrates, Lipids, Proteins, Nucleic Acids, ATP
CARBOHYDRATES
• “Hydrated Carbon”
• Monosaccharides are building blocks
• Disaccharides –double sugars
• Polysaccharides –branching chains
LIPIDS• More carbon & hydrogen than
oxygen
• Insoluble in water
• Saturated or unsaturated
• Triglycerides –fatty acids + glycerol
• Phospholipids –contain phosphorus
• Steroids –flat with interlocking rings
PROTEINS
• Amino acids are building blocks
• Amine + acid group + functional group (R)
• Most are complex in structure
Primary Secondary
Tertiary
NUCLEIC ACIDS• Building blocks are nucleotides
• Code for genes
• 5 types: adenine, guanine, cytosine, thyamine, uracil
• Deoxyribonucleic Acid (DNA) & Ribonucleic Acid (RNA)