C7 Flashcards
what bonds do Alkanes have?
C-C single bonds
whats the general formula of alkanes?
CnH2n+2
what are the first 4 alkanes?
-Methane CH4
-Ethane C2H6
-Propane C3H8
-Butane C4H10
Monkeys Eat Peanut Butter
what are the properties of hydrocarbons with shorter carbon chains?
-more runny
-less viscous
-more flammable
-lower boiling point
what is the formula for combustion?
hydrocarbon + oxygen —-> carbon dioxide + water
how is crude oil made ?
from the remains of dead plankton and other animals and plants buried in sand and mud over millions of years.
what are the uses of crude oil ?
fuel for transport e.g petrol and diesel
used to make other compounds such as polymers, lubricants, solvents and detergents
the longer the hydrocarbon the …… the boiling point
the higher
what is bromine water a test for?
an alkene
turns orange to colourless
what is cracking ?
the breaking down of large chain hydrocarbons into shorter chains
it produces alkenes that have a double bond
what are the two methods of cracking?
Catalytic cracking uses a temperature of approximately 550°C and a catalyst. known as a zeolite which contains aluminium oxide and silicon oxide.
Steam cracking uses a higher temperature of over 800°C and no catalyst.
what is fractional distillation?
Fractional distillation close fractional distillationIn fractional distillation a mixture of several substances, such as crude oil, is distilled and the evaporated components are collected as they condense at different temperatures. is used to separate crude oil. into simpler, more useful mixtures.
tests for gases:
1)Chlorine
2)Oxygen
3)Carbon dioxide
4)Hydrogen
1)chlorine bleaches damp litmus paper turning it white
2)if you put a glowing splint in a test tube containing oxygen it will relight
3)bubbling carbon dioxide through an aqueous solution of calcium hydroxide (limewater)causes the solution to turn cloudy
4)if you hold a little splint at the open of a test tube containing hydrogen it will create a ‘squeaky pop’
