ch2: kinetic particle theory

• properties of solids, liquids and gases

  A) fixed

  B) fixed

  C) not fixed

  D) not fixed

  E) fixed

  F) not fixed

  G) cannot

  H) cannot

  I) can

  
• particles are in constant motion, they are constantly moving and colliding with each other
• What is kinetic particle theory?

  
  

  -> all matter is made up of tiny particles ( atoms , molecules , ions ) , they are in constant and random motion , the speed of the particles depend on the amount of kinetic energy, there are spaces between the particles of matter
• Evidence for space between particles : alcohol and water

  From this experiment, it can be inferred that alcohol and water consist of particles of different sizes. There are spaces between the particles and on mixing, the smaller of the two kinds of particles occupy the spaces between the larger particles, resulting in a smaller total volume.

  
• How do we show diffusion?

  A) air

  B) bromine

  C) looks

  D) same

  
• Diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration.
• Do all gases diffuse at the same rate?

  Gases with lower molecular masses diffuse faster than those with higher molecular masses.
• molecular mass of hydrogen

  2
• molecular mass of oxygen

  32
• molecular mass of carbon dioxide

  44
• How does molecular mass affect diffusion?

  The smaller the relative molecular mass of the gas, the lighter it is, and the faster it moves. Hence, it can diffuse faster.
• How Do We Show That the Rate of Diffusion is Affected By Molecular Mass?

  The molecular mass of ammonia is 17. The molecular mass of hydrochloric acid is 36.5.

  Ammonia has a lower molecular mass than hydrogen chloride, and travels faster. Thus, ammonium chloride is formed further from the ammonia solution.

  
• Diffusion in liquids


  A small crystal of potassium manganate(Vll) is introduced into a beaker of distilled water. A deep purple solution forms at the bottom of the beaker. Diffusion slowly takes place until the solution becomes uniformly

  purple.

  
• Effect of Temperature on the Rate of Diffusion

  When temperature increases, the rate of diffusion increases.
• Kinetic Particle Theory : SOLID

  A) closely packed

  B) orderly manner

  C) vibrate

  D) fixed

  E) positions

  F) strong

  G) low

  
• Kinetic Particle theory : LIQUID

  A) closely packed

  B) disorderly

  C) random

  D) manner

  E) sliding over

  F) strong

  G) more kinetic energy

  
• Kinetic Particle Theory : GAS

  A) far apart

  B) randomly

  C) high

  D) speeds

  E) weak

  F) all

  G) a lot

  
• Changes in State of Matter and the Kinetic Particle Theory

  A) melting

  B) freezing

  C) boiling

  D) evaporation

  E) consideration

  F) sublimation

  
• changes in state of matter are reversible
• HEATING CURVE

  A) solid

  B) solid and liquid

  C) liquid

  D) liquid and gas

  E) gas

  F) boiling

  G) melting

  
• rate of diffusion

  • increases when temperature increases as more thermal energy is converted to kinetic energy of particles
  • decreases when particle mass increases as higher mass requires more kinetic energy to move at the same speed
• how do particles move?


  diffusion
• sublimation : substance changes directly from solid to gas
• vapour deposition: particles in gas are cooled and arranged directly into solid state.
• when answering the changes of state, must mention

  • energy conversions
  • movement of particles
  • temperature
  • forces of attraction
• why do solids have a fixed shape and volume?

  • particles in fixed positions in an orderly pattern
  • strong attractive forces prevents from breaking away from fixed positions
• why are solids not compressible?

  particles are closely packed together, little space to squeeze
• why is solid not able to flow?

  particles can only vibrate about in their fixed positions
• why does liquid have a fixed volume but not shape?

  • moderately strong attractive forces prevents from escaping positions
  • however, particles move about and slide past eachother freely
• why can liquid flow easily?

  particles move about and slide past eachother
• why is liquid not compressible?

  particles are arranged quite closely in a disorderly pattern, less space between them
• why does liquid take the shape of its container?

  particles are able to move about within confined spaces
• why does gas have no fixed volume or shape?

  • particles move freely and randomly in all directions
  • weak attractive forces cannot hold them in a confined space
• why is gas compressible?

  particles are far apart so there is much space between them
• why can gas flow easily?

  particles move freely at high speeds
• why does gas take the shape and volume of its container?

  particles are able to move freely in all directions to occupy the space in the container
• a physical change

  • does not produce new substances
  • involves energy being taken in from or given out to the surroundings
  • a substance melts,boils and freezes at the same fixed temperature under fixed conditions
• melting point = freezing point
• boiling point = point of condensation
• boiling occurs at boiling point while evaporation can occur at any temperature