Dorothy

• Gases are composed of molecules
• Gas molecules


  • The distances from molecule to another molecule are far greater than the molecules' dimensions
  • Molecules can be considered as spherical bodies which possess negligible mass and volume
• Gas molecules


  • They are in constant random motion in a straight line
  • They collide elastically with container walls and one another
• There are no attractive or repulsive forces between gas molecules
• As temperature increases


  The average kinetic energy of the molecules increases
• Gas


  A phase of matter with no definite shape and size, and can be compressed easily
• Properties of gases


  • Mass
  • Volume
  • Temperature
  • Pressure

  
• Volume of gases


  • The space occupied by the gases
  • Gases have the tendency to occupy all the spaces of the container that they are confined
• Temperature of gases


  • The measure of the hotness or coldness of an object
  • Proportional to the average kinetic energy of its molecules
  • Can be measured in Celsius or Kelvin

  
• Pressure of gases


  • The average effect of the forces of the colliding molecules
  • Can be expressed in unit atmosphere (atm), torr, psi, cmHg or mmHg
  • Can be quantified using the equation: P = F/A

  
• Boyle's Law


  The volume of gases is inversely proportional to pressure at a constant temperature

  
• Practical applications of Boyle's Law


  • Syringe
  • Human lungs
• Charles' Law


  The volume of gases is directly proportional to the temperature at a constant pressure

  
• Real-life applications of Charles' Law


  • Helium balloon
  • Bakery
• Boyle's Law: PV = k (at constant T and n)
• Charles' Law: V/T = k (at constant P and n)
• Volume of a gas


  Inversely proportional to its pressure, if temperature and amount of a gas are held constant

  
• Boyle's Law


  At constant temperature, the volume occupied by a fixed amount of gas is directly proportional to the reciprocal of pressure (1/P)

  
• Boyle's Law


  • PV = k
• Volume (V1) and Pressure (P1)


  V1 P1 = k

  
• Volume (V2) and Pressure (P2)


  V2 P2 = k

  
• Volume (V1) and Pressure (P2)


  V1 P2 = V2 P2
• Charles' Law


  At constant pressure, the volume of a fixed amount of gas is directly proportional to the Kelvin (K) temperature

  
• Mathematically, Charles' Law


  V = k * T
• Quantities and Symbols


  • No. of Moles (n, mol)
  • Volume (V, L)
  • Pressure (P, atm)
  • Temperature (T, K)
  • Universal Gas Constant (R, L.atm/mol.K)

  
• When analysing markets, a range of assumptions are made about the rationality of economic agents involved in the transactions
• The Wealth of Nations was written

  1776
• Rational


  (in classical economic theory) economic agents are able to consider the outcome of their choices and recognise the net benefits of each one
• Rational agents will select the choice which presents the highest benefits
• Producers act rationally by


  Selling goods/services in a way that maximises their profits
• Workers act rationally by


  Balancing welfare at work with consideration of both pay and benefits
• Governments act rationally by


  Placing the interests of the people they serve first in order to maximise their welfare
• Rationality in classical economic theory is a flawed assumption as people usually don't act rationally
• Demand curve shifting right

  Increases the equilibrium price and quantity
• Marginal utility


  The additional utility (satisfaction) gained from the consumption of an additional product
• If you add up marginal utility for each unit you get total utility
• Biomolecules are organic compounds made by living things
• Major categories of biomolecules


  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids
• Carbohydrates


  One of the main sources of energy for living organisms, consisting of carbon, hydrogen, and oxygen
• Classifications of carbohydrates


  • Monosaccharides
  • Disaccharides
  • Polysaccharides