Kinetic molecular theory

• Who is the science teacher for today?

  Mom Deya
• What is the main topic of discussion this week?

  Kinetic molecular theory and gas laws
• Why do we need the kinetic molecular theory?

  To understand gas properties at the molecular level
• What does the first assumption of the kinetic molecular theory state?

  Gases are composed of molecules
• How are the distances between gas molecules described?

  Far greater than the molecules' dimensions
• What is the second assumption of the kinetic molecular theory?

  Gas molecules are in constant random motion
• What type of collisions occur between gas molecules?

  Perfectly elastic collisions
• What does a perfectly elastic collision imply?

  No loss of kinetic energy occurs
• What is the third assumption of the kinetic molecular theory?

  Attractive and repulsive forces are absent
• How are charges treated in the kinetic molecular theory?

  Forces from charges are considered insignificant
• What is the fourth assumption of the kinetic molecular theory?

  Average kinetic energy is related to temperature
• What happens to temperature when gas molecules move faster?

  Temperature increases
• What is Avogadro's law about?

  It relates the number of moles and volume of gas
• What does Avogadro's law state about the relationship between moles and volume?

  They are directly related
• Under what conditions does Avogadro's law apply?

  When pressure and temperature are constant
• How is Avogadro's law mathematically expressed?

  $\frac{v_1}{n_1} =$$\frac{v_2}{n_2}$
• What does \(v_1\) represent in Avogadro's law?

  Initial volume
• What does \(n_1\) represent in Avogadro's law?

  Initial amount of gas in moles
• If a 1.2 liter sample contains 0.07 mole of nitrogen, what is \(n_2\) in a 20 liter sample?

  1.17 moles
• How do you calculate \(n_2\) using Avogadro's law?

  Substitute values into the equation
• What does the ideal gas law combine?

  All previous gas laws discussed
• Who is the scientist behind the ideal gas law?

  Benoit Paul Émile Clapeyron
• What does Boyle's law state?

  Volume is inversely proportional to pressure
• What does Charles's law state?

  Volume is directly proportional to temperature
• What does Avogadro's law state about volume?

  Volume is directly proportional to amount of gas
• How is the ideal gas law expressed mathematically?

  $PV =$$nRT$
• What must pressure be in for the ideal gas law?

  Atmospheres
• What must volume be in for the ideal gas law?

  Liters
• What must the amount of substance be in for the ideal gas law?

  Moles
• What must temperature be in for the ideal gas law?

  Kelvin
• What is the value of the universal gas constant \(R\)?

  0.0821 L·atm/(mol·K)
• How do you convert Celsius to Kelvin?

  Add 273.15 to Celsius
• How many moles are present in 6.5 liters at 2.9 atmospheres and 27 degrees Celsius?

  0.76 moles
• What is the temperature when 0.654 moles occupy 15.2 liters at 1.95 atmospheres?

  552 Kelvin
• What are the assumptions of the kinetic molecular theory?

  1. Gases are composed of molecules.
  2. Molecules are in constant random motion.
  3. Collisions are perfectly elastic.
  4. Attractive and repulsive forces are absent.
  5. Average kinetic energy is related to temperature.
• What are the properties of the ideal gas law?

  • Combines Boyle's, Charles's, and Avogadro's laws.
  • Relates pressure, volume, temperature, and amount of gas.
  • Must use specific units: atm, L, mol, K.
• What are the steps to solve problems using the ideal gas law?

  1. Identify known values (P, V, n, T).
  2. Convert temperature to Kelvin.
  3. Substitute values into the equation \(PV = nRT\).
  4. Solve for the unknown variable.