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CHEMISTRY COMES ALIVE

This comprehensive overview of basic chemistry explores key concepts such as matter, energy, atomic structure, and chemical reactions. Matter is defined as anything that has mass and occupies space, with mass remaining constant regardless of gravity. Energy is discussed in its various forms, including kinetic, potential, and chemical energy. The atomic structure, including protons, neutrons, and electrons, is explained, alongside the distinction between elements, compounds, and mixtures. Additionally, chemical bonding types and the dynamics of chemical reactions are reviewed, highlighting the principles of chemical equilibrium.

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CHEMISTRY COMES ALIVE

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  1. CHEMISTRY COMES ALIVE BASIC CHEMISTRY

  2. DEFINITION OF CONCEPTS MATTER AND ENERGY

  3. MATTER • ANYTHING THAT HAS MASS AND OCCUPIES SPACE • MASS=AMOUNT OF MATTER IN THE OBJECT • MASS REMAINS CONSTANT REGARDLESS OF GRAVITY

  4. STATES OF MATTER • SOLID • LIQUID • GAS

  5. ENERGY • ENERGY IS THE CAPACITY TO DO WORK AND EXISTS IN 2 FORMS • KINETIC ENERGY – ENERGY OF MOTION • POTENTIAL ENERGY – STORED ENERGY

  6. FORMS OF ENERGY • CHEMICAL ENERGY – ENERGY STORED IN CHEMICAL BONDS • ELECTRICAL ENERGY – RESULTS FROM MOVEMENT OF CHARGED PARTICLES • MECHANICAL ENERGY – INVOLVED WITH MOVING MATTER • RADIANT ENERGY – ENERGY THAT TRAVELS IN WAVES • ENERGY CAN BE CONVERTED FROM ONE FOR TO ANOTHER

  7. COMPOSITION OF MATTER ATOMS AND ELEMENTS

  8. BASIC TERMS • ELEMENTS CANNOT BE BROKEN DOWN INTO SIMPLER SUBSTANCES BY ORDINARY CHEMICAL MEANS • C,H,O,AND N – 96% OF BODY WEIGHT • ATOMS – SMALLEST PARTICLES OF AN ELEMENT THAT RETAIN THE CHARACTERISTICS OF THAT ELEMENT • ELEMENTS ARE DESIGNATED BY 1 OR 2 LETTER ATOMIC SYMBOLS

  9. ATOMIC STRUCTURE • ATOM HAS NUCLEUS WITH PROTONS(+, 1 AMU) AND NEUTRONS(NO CHARGE, 1 AMU) • ELECTRONS – HAVE A NEG. CHARGE AND MOVE AROUND THE NUCLEUS.(0 AMU) • ATOMS ARE ELECTRICALLY NEUTRAL (PRO. = ELEC.) • PLANETARY MODEL – 2-D • ORBITAL MODEL – 3-D

  10. IDENTIFYING ELEMENTS • ELEMENTS ARE IDENTIFIED BASED ON THEIR NUMBER OF P,N, AND E.

  11. ATOMIC NUMBER • ATOMIC NUMBER = # OF PROTONS • SINCE # PROTONS = # ELECTRONS IN AN ELECTRICALLY NEUTRAL ATOM, THE ATOMIC # ALSO TELLS US # OF ELECTRONS

  12. MASS # AND ISOTOPES • MASS # = PROTONS + NEUTRONS • ELECTRON IS WEIGHTLESS SO IT IS IGNORED WHEN CALCULATING MASS # • ISOTOPES – VARIATIONS OF AN ATOM THAT HAVE THE SAME NUMBER OF PROTONS, BUT DIFFERING NUMBERS OF NEUTRONS

  13. ATOMIC WEIGHT • AVERAGE OF THE RELATIVE WEIGHTS OF ALL OF THE ISOTOPES OF AN ELEMENT

  14. RADIOISOTOPES • HEAVIER, UNSTABLE ISOTOPES OF AN ELEMENT THAT SPONTANEOUSLY DECOMPOSE INTO MORE STABLE FORMS • TIME REQUIRED FOR A RADIOACTIVE ISOTOPE TO LOSE ONE-HALF OF ITS RADIOACTIVITY IS CALLED THE HALF-LIFE

  15. HOW MATTER IS COMBINED MOLECULES AND MIXTURES

  16. MOLECULES AND COMPOUNDS • MOLECULE – A COMBINATION OF TWO OR MORE ATOMS • 2 OR MORE ATOMS OF THE SAME ELEMENT IS CALLED A MOLECULE OF THAT ELEMENT • COMPOUND – 2 OR MORE ATOMS OF DIFFERENT ELEMENTS COMBINED

  17. MIXTURES • SUBSTANCES MADE OF 2 OR MORE COMPONENTS MIXED PHYSICALLY • SOLUTIONS ARE HOMOGENEOUS MIXTURES OF COMPOUNDS THAT MAY BE SOLID, LIQUID, OR GAS • SOLUTIONS HAVE SOLVENTS AND SOLUTES • MAY BE DESCRIBED BY THEIR CONCENTRATIONS (MOLARITY)

  18. MIXTURES CONT. • COLLOIDS – HETEROGENEOUS MIXTURES • SUSPENSIONS – HETEROGENEOUS MIXTURES WITH LARGE, OFTEN VISIBLE SOLUTES THAT TEND TO SETTLE OUT

  19. DISTINGUISHING MIXTURES AND COMPOUNDS • MAIN DIFFERENCE – NO CHEMICAL BONDING BETWEEN MOLECULES OF A MIXTURE • MIXTURES CAN BE SEPARATED BY PHYSICAL MEANS, COMPOUNDS MUST BE SEPARATED BY CHEMICAL MEANS • HOMOGENEOUS VS. HETEROGENEOUS

  20. CHEMICAL BONDS • AN ENERGY RELATIONSHIP BETWEEN THE ELECTRONS OF REACTING ATOMS

  21. ROLE OF ELECTRONS IN CHEMICAL BONDING • ELECTRONS OCCUPY ELECTRON SHELLS AROUND THE NUCLEUS THAT REPRESENT DIFFERENT ENERGY LEVELS • EACH ELECTRON SHELL HOLDS A SPECIFIC # OF ELECTRONS AND TEND TO BE FILLED FROM CLOSEST TO THE NUCLEUS OUT. • EXCEPT FOR THE 1ST ENERGY LEVEL, ATOMS ARE STABLE WITH EIGHT ELECTRONS IN THEIR VALENCE SHELL (THE OCTET RULE)

  22. TYPES OF CHEMICAL BONDS

  23. IONIC BONDS • CHEMICAL BONDS THAT TRANSFER ONE OR MORE ELECTRONS FROM ONE ATOM TO ANOTHER • IONS ARE CHARGED PARTICLES, EITHER ANIONS (NEG) OR CATIONS (POS) • CRYSTALS ARE LARGE STRUCTURES OF CATIONS AND ANIONS HELD TOGETHER BY IONIC BONDS.

  24. COVALENT BONDS • SHARE ELECTRONS • NONPOLAR COVALENT BONDS – SHARE ELECTRONS EVENLY • POLAR COVALENT BONDS – SHARE ELECTRONS UNEVENLY (OFTEN REFERRED TO AS A DIPOLE)

  25. HYDROGEN BONDS • WEAK ATTRACTIONS THAT FORM BETWEEN PARTIALLY CHARGED ATOMS FOUND IN POLAR MOLECULES • HYDROGEN BONDS BETWEEN WATER MOLECULES CAUSES SURFACE TENSION

  26. CHEMICAL REACTIONS • OCCUR WHENEVER BONDS ARE FORMED, REARRANGED, OR BROKEN • A CHEMICAL EQUATION DESCRIBES WHAT HAPPENS IN A REACTION • INCLUDES REACTANTS AND PRODUCTS • MUST BE BALANCED

  27. PATTERNS OF CHEMICAL REACTIONS • SYNTHESIS (COMBINATION) RXN – LARGER MOLECULES ARE FORMED FROM SMALLER MOLECULES • DECOMPOSITION RXN – A MOLECULE IS BROKEN DOWN INTO SMALLER MOLECULES • EXCHANGE (DISPLACEMENT) RXN – INVOLVE BOTH SYN. AND DECOMP. • OXIDATION-REDUCTION RXN – SPECIAL ECHANGE RXNS IN WHICH ELECTRONS ARE EXCHANGED BETWEEN REACTANTS

  28. ENERGY FLOW IN CHEM. RXNS • EXERGONIC RXNS RELEASE ENERGY AS A PRODUCT, WHILE ENDERGONIC RXNS ABSORB ENERGY

  29. REVERSIBILITY OF CHEMICAL RXNS • ALL CHEM RXNS ARE THEORETICALLY REVERSIBLE • WHEN THE RATE OF THE FORWARD RXN = THE RATE OF THE REVERSE RXN, THE RXNS HAVE REACHED A CHEMICAL EQUILIBRIUM

  30. FACTORS INFLUENCING RATE OF CHEMICAL RXNS • CHEMICALS REACT WHEN THEY COLLIDE WITH ENOUGH FORCE TO OVERCOME THE REPULSION BY THEIR ELECTRONS • INCREASE IN TEMP. INCREASES RATE • SMALLER PARTICLES – FASTER RATE • HIGHER CONCENTRATION OF REACTANTS – FASTER RATE • CATALYSTS INCREASE RATE WITHOUT TAKING PART IN THE RXN

  31. BIOCHEMISTRY INORGANIC COMPOUNDS

  32. WATER • MOST IMPORTANT INORGANIC MOLECULE, MAKES UP 60 TO 80% OF THE VOLUME OF MOST LIVING CELLS • HAS A HIGH HEAT CAPACITY • HIGH HEAT OF VAPORIZATION • POLAR MOLECULE • UNIVERSAL SOLVENT • IMPORTANT REACTANT • FORMS A PROTECTIVE CUSHION AROUND ORGANS

  33. SALTS • IONIC COMPOUNDS • WHEN DISSOLVED IN WATER, THEY DISSOCIATE INTO THEIR COMPONENT IONS

  34. ACIDS AND BASES • ACIDS – AKA PROTON DONORS, DISSOCIATE IN H2O TO YIELD HYDROGEN IONS AND ANIONS • BASES – AKA PROTON ACCEPTORS, ABSORB HYDROGEN IONS • PH UNITS – RELATIVE CONCENTRATION OF HYDROGEN IONS • GREATER HYDROGEN ION CONCENTRATION – ACIDIC • GREATER HYDROXYL ION CONCENTRATION – BASIC (ALKALINE)

  35. ACIDS AND BASES CONT. • NEUTRALIZATION – WHEN AN ACID AND A BASE ARE MIXED TOGETHER. DISPLACEMENT REACTION THAT FORMS SALT AND WATER • BUFFERS – RESIST LARGE FLUCTUATIONS IN PH THAT WOULD BE DAMAGING TO LIVING TISSUES

  36. BIOCHEMISTRY ORGANIC COMPOUNDS

  37. CARBOHYDRATES • GROUP OF MOLECULES INCLUDING SUGARS AND STARCHES • CONTAIN CARBON, HYDROGEN, AND OXYGEN • MAIN FUNCTION IS TO PROVIDE CELLULAR FUEL • MONOSACCHARIDES ARE SINGLE RING STRUCTURES (SIMPLE SUGARS) • DISACCHARIDES – 2 MONOSACCHARIDES JOINED BY DEHYDRATION SYNTHESIS • POLYSACCHARIDES – LONG CHAINS OF MONOSACCHARIDES JOINED BY DEHYDRATION SYNTHESIS

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