Vapour pressure

Question 1

what is vapour pressure

Answer 1

pressure exerted by a pure substance in a system containing only the vapour and condensed phase of a substance

Question 2

what are flammability limits

Answer 2

• the limits within which a combustion reaction occurs
  at the upper explosive limit - gas will burn
  at the lower explosive limit - gas ignites and burns

Question 3

calculating the lower flammabilty limit

Answer 3

stoichiometric ratio of fuel : oxygen x 100/21

Question 4

flash point

Answer 4

• minimum temperature at which vapour produced by a liquid can be ignited momentarily in air
  low flash point = higher vapour temperature

Question 5

fire point

Answer 5

minimum temperature at which the vapour produced by a liquid sustains combustion after ignition in air
- often a few degrees higher than the flash point

Question 6

Ignition temperature

Answer 6

the temperature something will spontaneously ignite (auto ignition)
reflects the Ea