Alkanes QP Flashcards
(17 cards)
Are zeolyte catalysts used in thermal cracking? [1]
[1] No
Equaton for a reaction that removes nitrogen in a catalytic converter? [1]
[1] 2NO + 2CO –> N2 + 2CO2
Suggest one reason why a value for the enthaply of combustion of a liquid alkane is different from other values. [1]
[1] Alkene is not gaseous
OR
[1] Energy needed to convert it into a gas
Conditions and Products of Catalytic Cracking? [2]
[1] Slight pressure, high temperature
[2] Mainly branches alkanes and aromatics.
Which cracking type is a zeolite catalyst used in? [1]
[1] Catalytic Cracking
Why should sulfur cimpounds be removed before heating? [2]
[1] Form sulfur dioxide
[2] Which causes acid rain
One large important substance manafactured from propene [1]
[1] Polypropene
OR
[1] Proposal
Evidence of thermal cracking? [1]
[1] Mostly alkenes formed
What is a use of ethene? [1]
[1] Making plastics
How is nitrous oxides formed in the atmosphere? [2]
[1] Gaseuos nitrogen and oxygen in the air react
[2] At high temperatures
Equation of NO to NO2 [1]
[1] 2NO + O2 –> 2NO2
Equation between NO2, H2O and O2 for nitric acid. [2]
4NO2 + 2H2O + O2 –> 4HNO3
Outline the essential features of the fractional distillation of crude oil that enable the crude oil to be separated into fractions [4]
[1] Fractions or hydrocarbons or compounds have different boiling points
[2] depends on size/ Mr/ chain length
[3] Temp gradient in tower or column / cooler at top of column
[4] Higher bp / larger or heavier molecules at bottom
What is cracking? [1]
Large molecules or compounds or long chain hydrocarbons (broken) into smaller molecules or compounds or smaller chain hydrocarbons
What is meant by structural isomers? [2]
[1] The same molecular formula
[3] Different sructural formula
Explain why NO is formed in petrol engines but is not readily formed when petrol burns in the open air [3]
[1] NO formed by reaction between N2 and O2 from the air
[2] High combustion temperature
[3] provides EA or sufficient heat
Why are some reactions carried out in industry? [1]
To make products which are in greater demand
