Chapter: 1 Stoichiometric RelationshipsTitle: Particulate Nature of Matter and Chemical ChangeLearning Objectives:

• Understand how energy changed is involved when there is a change of state.

• Understand that atoms of different elements combine in fixed ratios to form compounds, which have different properties from their component elements.

• Understand why mixtures are either homogeneous or heterogeneous.

Q. What happens to the particles in water for it to become:

•Ice?•Steam?

Solids Liquids Gases

Distance between particles

Arrangement

Shape

Volume

Movement

Speed of Movement

Energy

Forces of attraction

TASK: Fill in the table – Properties of the three states of matter. Use the mixed up words below

Strongest Close Together Vibrate

Random Fixed Not fixed – Fills container

Move around each other

Weaker Fixed

Regular Fixed Not Fixed – Takes container shape

Random Not Fixed Weakest

Slowest Move in all directions

Faster

Lowest Highest Far Apart

Close (ish) Fastest Higher

States of Matter

Sublimation is the direct inter conversion of solid to gas without going through the liquid state. Examples of this are:

Iodine, Carbon dioxide and Ammonium chloride (all at atmospheric pressure)

Deposition is the direct conversion of gas to solid without going through the liquid state. Examples of this are:

Snow and Frost

NOTE! Evaporation and boiling are not the same thing! Evaporation occurs only at the surface and takes place at temperatures below the boiling point.

Q. Where do you think boiling takes place? Why does boiling a liquid produce bubbles?

Boiling happens when particles leave throughout the body of the liquid – which is why bubbles occur.

Boiling occurs at a specific temperature, determined by when the vapour pressure reaches the external pressure.

Q. Why does a butane gas camping stove store the butane as a liquid? (Relate back to the what the graph showed you)

TASK: How can this temperature versus energy input graph be interpreted in terms of particle theory?

Put the statements in the correct order by reading them carefully. State names have been blanked out so it’s not so easy!

Letter PhaseWhat is going on at this phase?

a-b

b-c

c-d

d-e

e-f

Letter Phase What is happening at each phase