SCIENCE

• Gas


  State of matter that has no definite shape and volume, occupies all spaces available in its container, is compressible, exerts pressure, expands when heated and contracts when cooled, has negligible intermolecular forces so diffuses easily
• Measurable properties of gas

  • Volume
  • Pressure
  • Temperature
• Volume of gas

  Equal to the volume of its container, common units are liter (L), milliliter (mL), cubic meter (m3) and cubic centimeter (cm3)
• Pressure of gas

  Force exerted by gas molecules on the walls of its container divided by the surface area of the container, common units are atm, N/m2 (Pa), torr, mmHg, psi
• Temperature of gas


  Average kinetic energy of the gas particles, usually expressed in °C, °F, K (Kelvin is used in computations)
• Standard conditions for gas

  Standard temperature is 0°C or 273K, standard pressure is 1 atm, 1 mole of gas occupies 22.4 L
• Relationship between volume and pressure of gas in an enclosed container

  1. As pressure increases, volume decreases

  2. As pressure decreases, volume increases
• Inhaling


  Diaphragm muscles contract, thoracic cavity expands, volume increases, pressure decreases
• An argon gas occupies 56.2 L at 760 torr. If the volume of gas is decreased to 1/4 of the original volume, the final pressure can be calculated.
• At 0°C and 5 atm, a gas sample occupies 75 L. The gas is compressed to a final volume of 30 L at 0°C. The final pressure can be calculated.
• Gas Pressure


  Force acting on a specific area
• Volume


  Three-dimensional space occupied by a gas
• Temperature


  Measure of warmth or coldness
• Quantity


  Measured in moles (mol)
• Boyle's Law

  Pressure is inversely proportional to volume at constant temperature
• Boyle's Law Equation

  P1V1 = P2V2
• Charles's Law


  Volume is directly proportional to temperature at constant pressure
• Charles's Law Equation

  V1 / T1 = V2 / T2
• Mole


  6.022 x 10^23
• Monosaccharides


  • Glucose (blood sugar)
  • Fructose (fruit sugar)
  • Galactose (found in milk with glucose)
• Disaccharides


  • Maltose (malt sugar)
  • Lactose (milk sugar)
  • Sucrose (table sugar)
• Polysaccharides


  • Starch
  • Glycogen
  • Cellulose
  • Chitin
• Starch


  • Used for energy storage in plants
  • Provides a quick form of energy for the body
  • Used for energy storage in animals and muscles in the form of glycogen
• Glycogen


  Stores glucose or energy when the body doesn't need it
• Cellulose


  Found in plants, in cell walls, and bark of trees
• Chitin


  • Gives us fiber
  • Forms the exoskeleton of certain insects and crustaceans
• Iodine Test for Starch

  1. Positive result: color change ranging from violet to black

  2. Negative result: yellow color (no change) of the iodine solution
• Benedict's Test


  1. Green: 0.1 to 0.5 percent sugar in solution

  2. Yellow: 0.5 to 1 percent sugar present

  3. Orange: 1 to 1.5 percent sugar present

  4. Red: 1.5 to 2.0 percent sugar present

  5. Brick red: more than 2 percent sugar present in solution
• Proteins


  • Body-building molecules
  • Transport molecules in and out of the cell
  • Control the speed of chemical reactions
  • Used for growth and repair
• Amino acids


  Building blocks of proteins
• Protein general formula


  RCH(NH)COOH, R is a side chain, usually an amino acid
• Proteins


  • Albumin
  • Hemoglobin
• Biuret Test


  1. Determines the presence of a peptide bond (chemical bond between amino acids)

  2. Negative result: Biuret reagent remains blue

  3. Positive result: Biuret reagent changes from blue to purple
• Nucleic Acids


  Biomolecular components of hereditary materials and are present in DNA
• Nucleotides

  Building blocks of nucleic acids
• Elements in nucleic acids

  1. H-O-N-P (carbon, hydrogen, oxygen, nitrogen, phosphorus)
• Lipids


  • Energy-giving molecules
  • Stored-energy molecules
  • Store more energy than carbohydrates and proteins
• Fatty acids


  Building blocks of lipids
• Lipids


  • Provide mechanical protection for the internal organs of the body
  • Serve as waterproof covering in some plants and animals
  • Hydrophobic and do not dissolve in water
• Lipids


  • Steroids
  • Cholesterol
  • Oils
  • Fats
  • Nuts
  • Waxes