### substance | mixture | suspension:

Vapour
* Some vapour affects weather
  - penetrates wombs
* acts as a respiratory, skin and eye irritant.
* are highly flammable and creep at ground level
  - in equilibrium with the solids or liquids from which they originate
  - reactive with most organics
* becomes water.
* condenses into droplets.
* contributes to precipitation.
* enters atmospheres.
* forms an explosive mixture with air
  - cumulonimbus clouds
* goes through the bubble cap and bubbles through condensed petroleum.
* is harmful on prolonged exposure or in high concentration
  - heavier. than air and anaesthetic
  - narcotic at high concentrations
  - physical change
  - seen as the cold liquid cools the beaker and surrounding air
  - severe irritant to the eyes, mucous membranes and respiratory tract
* represent the most insidious of hazards.
* rises into air.

### substance | mixture | suspension | vapour:

Water vapour
* Most water vapour becomes water
  - enters atmospheres
* absorbs the sun's radiation.
* by-product of any combustion process.
* comes from natural and human-induced respiration, transpiration, and evaporation
* condenses into droplets.
* contains an enormous amount of latent heat
  - dimer, trimer and a little tetramer
* decisive element in formation of the polar stratospheric clouds.
* decreases sharply, whilst ozone concentrations increase.
* diffuses out through the stoma down a diffusion gradient.
* enters the atmosphere and circulates with the air
  - by evaporation from surface bodies of water
* forms clouds
* is actually less dense than air
  - an important constituent of the atmosphere
  - essentially invisible as a gas
  - light and rises up towards the sky
  - located in clouds
  - the largest contributor to the natural greenhouse effect in South Africa
* is the main greenhouse gas, so the warming trend is compounded
  - major radiative gas based on the amount in the atmosphere
  - most important green house gas
* is the most important greenhouse gas of all
* starts to condense when the atmosphere can hold no more water i.e. it is saturated.

Molecular substance
* Some molecular substances find in mangos.
* are often soluble in organic solvents - which are themselves molecular
  - the only ones with low boiling points

Molten material
* can cause severe burns.
* is cooled, causing a solid to form at one end of the sample.

### substance:

Natural material
* All natural materials can dry out and become dull looking, shrink, or crack in arid climates
  - contain salt in small quantities
* Many natural materials are toxic to humans.
* Most natural materials contain phases.
* are graybodies whose temperatures depart somewhat from perfect blackbodies
  - sensitive to changes in heat and humidity
* can be just as toxic as synthetics.
* consist of many different chemicals, many of which are very similar.
* found in the environment also induce plant resistance as well.
* have many color variations.
* reflects the environment.

Natural resin
* Some natural resin acts as electric insulators
* are secretions from plants, mainly trees
  - yellow to brown in color
* is an organic compound

### substance | natural resin:

Benjamin
* are companies.
* is natural resin