Chapter 1 Flashcards
What is petroleum
a complex mixture of hydrogen and carbon molecules
What is the simplest hydrocarbon
Methane
Hyrdocarbon molecules join together to form what
chains
Chains of less than five carbons exist as what
gases
Chains of five and twenty exist as what
liquids
Chains of over twenty exist as what
solids
Hydrocarbon molecules can form into chains of different shapes. This will
give substances with the same carbon count different characteristics.
What is volatility
tendency of a substance to evaporate at normal temperatures.
It is the ________ given off from a substance that burns, not the substance
itself
Vapour
When is vapour given off
evaporation process
When evaporation equals condensation….
Saturation conditions exist
The pressure exerted when saturation occurs is the _________. _________. ________ (SVP) and this is related to temperature
Saturated vapour pressure
If SVP equals atmospheric pressure (approx 1 bar) then…..
the liquid will boil
Evaporation takes place from the liquid surface, boiling occurs from…..
within the liquid
Volatile substances evaporate…
rapidly
Non-volatile substances evaporate
slowly
Evaporation is affected by
x 4
Evaporation is affected by:
1. Temperature
2. Surface Area
3. Liquid to vapour ratio
4. Turbulence
What does TVP mean
True Vapour Pressure
What is TVP
is the highest pressure possible but is difficult to calculate
What does RVP stand for
Reid Vapour Pressure
What does RVP do
is a useful test for comparing the volatility of
different products but does not give an indication of the likely vapour generation within a cargo tank
Hydrocarbon vapour is usually denser than…
air
What is flashpoint
is the lowest temperature at which a substance gives off enough vapour to briefly ignite when an external source of ignition is applied
What is flashpoint a measure of
is a measure of a substances flammability
