Monday, July 10, 2017

1.1: Understand the Three States of Matter in Terms of Arrangement, Movement and Energy of the Particles



THREE STATES OF MATTERS:
s

SOLID
LIQUID
GAS
DIAGRAM
ARRANGEMENT
Close together in regular arrangement
Close together in free arrangement
Far apart in random arrangement
MOVEMENT
Vibrate on the spot
Moves around each other
Moves quickly in all directions
ENERGY
Small amount of kinetic energy
Moderate amount of kinetic energy
Large amount of kinetic energy

1.2: Understand the Interconversions between the Three States of Matter in Terms of: The Names of the Interconversions, How they are Achieved, the Changes in Arrangement, Movement and Energy of the Particles



INTERCONVERSIONS BETWEEN STATES OF MATTER:




Diagram showing the interconversions between the states of matter



EXPLANATION:

CHANGE
EXPLANATION
SOLID → LIQUID

MELTING
  • Heat the Solid until it Melts
  • Particles gain kinetic energy and vibrates faster, allowing particles to overcome forces of attraction that hold them together in the solid
  • Regular pattern is broken down and particles can now slide past one another

LIQUID → SOLID

FREEZING
  • Cool the Liquid until it Freezes
  • Particles lose kinetic energy, allowing forces of attraction between the particles to hold them together
  • Particles arrange themselves into a regular pattern and are no longer able to slide past one another

LIQUID → GAS

EVAPORATING
  • Heat the Liquid until it Boils
  • Particles gain kinetic energy and move further apart, causing the forces of attraction between them to be completely broken and escape from liquid

GAS → LIQUID

CONDENSING
  • Cool the Gas until it Condenses
  • Particles lose kinetic energy and vibrates faster, allowing forces of attraction to bring particles closer together
  • Particles eventually clump together to form a liquid

SOLID → GAS

SUBLIMATION
  • Heat the Solid until it Sublimes
  • Particles gain kinetic energy and vibrates faster, causing forces of attraction between particles to be completely broken and escape from solid

1.3: Understand How the Results of Experiments Involving the Dilution of Coloured Solutions and Diffusion of Gases can be Explained



DILUTION OF COLOURED SOLUTIONS

Diagram Showing a Crystal of Potassium Manganate (VII) Dissolving in Water
METHOD:

  • Fill beaker with water
  • Add a Crystal of Potassium Manganate (VII) and record observations

RESULTS:

  • When Potassium Manganate (VII) Crystals are Dissolved in Water, a Purple Solution Forms
  • This occurs as both Water and Potassium Manganate (VII) Particles are moving Freely and sliding over each other, allowing them to mix to form a solution with a weaker colour than the original Crystal (original dye)
  • As Potassium Manganate (VII) particles are less concentrated, the final colour will be weaker





DIFFUSION OF GASES

Diagram showing the Diffusion of Bromine Gas with Air
METHOD:

  • Place a jar of air on top of a jar of Bromine
  • Allow time for diffusion to take place and record observations

RESULTS:

  • Overtime, Bromine Gas will diffuse upwards into the jar of air
  • This occurs as large gaps between Air and Bromine particles allows them to move randomly and collide with each other, mixing together to form a gas with lighter shade of brown
  • As Bromine particles are less concentrated, the final colour will be weaker

1.4: Know What is Meant by the Terms: Solvent, Solute, Solution, Saturated Solution



DEFINITION:
s
TERM
DEFINITION
SOLVENT
Substance that dissolves a solute
E.g, In salt and water solution, water is the solvent
SOLUTE
Substance that dissolves in a solvent
E.g, In salt and water solution, salt is the solute
SOLUTION
Mixture formed by a solvent and solute
SATURATED SOLUTION
Solution where no more solute can dissolve (any more solute that is added will settle at the bottom)

1.5C: Know What is Meant by the Term Solubility in the Units g Per 100g of Solvent



SOLUBILITY: How much of a substance will dissolve in a given volume of a solvent (shown in the units of g per 100g of solvent)
s
  • If a substance is soluble, it will dissolve in a given amount of solvent (liquid)
  • Solubility increases as temperature and pressure increases



EXAMPLES OF SOLUBILITY OF SUBSTANCES IN WATER AT 20°C:
s
SOLUTE
SOLUBILITY
SODIUM CHLORIDE
36
COPPER (II) SULPHATE
32
LEAD (II) IODIDE
0.07
LEAD (II) NITRATE
54

1.6C: Understand How to Plot and Interpret Solubility Curves



SOLUBILITY: How much of a substance will dissolve in a given volume of a solvent (shown in the units of g per 100g of solvent)
s
  • If a substance is soluble, it will dissolve in a given amount of solvent (liquid)
  • Solubility increases as temperature and pressure increases




EXAMPLE OF INTERPRETING SOLUBILITY CURVES:




SOLID
EXPLANATION
A
As temperature increases, solubility of Solid A increases the most
B
As temperature increases, solubility of Solid B increases but at a slower rate than Solid A
C
Temperature does not affect the solubility of Solid C

1.7C: Practical: Investigate the Solubility of a Solid in Water at a Specific Temperature



SOLUBILITY: How much of a substance will dissolve in a given volume of a solvent (shown in the units of g per 100g of solvent)

INVESTIGATING SOLUBILITY OF SOLIDS AT SPECIFIC TEMPERATURES

Diagram showing a Solid in Set Temperature of Water to Measure Solubility
METHOD:

  • Set water bath to specific temperature
  • Use water from water bath and add into Beaker
  • Add solid into the beaker and measure time taken for Solid to dissolve

RESULT:

  • As temperature of Water increases, time taken for Solid to dissolve will decrease (more soluble)
  • This occurs as increase in temperature increases the kinetic energy of particles, overcoming the intermolecular forces of attraction between solid particles
  • This causes particles to break apart, increasing solubility of Solid as a result