Chem Flashcards
When a substance combusts, it reacts with …
Oxygen
C + O2 –> …
CO2
Write a balanced equation for the combustion of carbon.
C + O2 –> CO2
Write a balanced equation for the combustion of hydrogen.
H2 + 1/2 O2 –> H2O
What does a hydrocarbon produce when it combusts ?
Carbon dioxide + water
Crude oil is…
A mixture of many different hydrocarbons
What can the trend of melting and boiling points of the Fractions be explained by ?
Intermolecular forces
What does fractional distillation produce ?
Long chain hydrocarbons
What industrial method is used to produce a mixture of smaller molecules after fractional distillation ?
Cracking
Aluminium oxide
C18H38 —-> C10H22 + ……….
Catalyst
C8H16
In cracking, what allows the reaction to take place at a lower temp ?
A catalyst
A homologous series is …
A family of compounds with the same general formula and similar chemical properties
Name this alkane
H. H. H. H
I. I. I. I
H-C-C-C-C-H
I I. I. I
H. H. H. H
Butane
Name this alkane
H
I
H- C- H
H H I H
I I I I
H-C - C - C - C-H
I. I. I. I
H. H. H. H2 methyl butane
C5H12
What is the formula mass of pentane ?
C5H12
= (12 x 5) + (1x12)
= 60 + 12
= 72 AMU
Write a balanced equation for the combustion of hexane
C6H14 + 9.5 O2 –> 6 CO2 + 7 H2O
Draw Propene
H. H. H.
I. I. I.
H-C-C=C
I I.
H. H.What is the general formula for the cycloalkanes ?
CnH2n
What is the general formula for the cycloalkenes ?
CnH2n-2
What is the general formula for the alkanes ?
CnH2n+2
What is the general formula for the alkenes?
CnH2n
What are isomers ?
Compounds with the same molecular formula but different structural formula
Cycloalkanes and alkenes with the same number of carbons are….
Isomers
Are alkanes saturated ?
Yes
Are alkenes saturated ?
No
What happens to bromine solution when an alkene is added
It decolourises
What happens when an alkene reacts with hydrogen
An alkane is formed
What is another name for alcohols
Alkanols
Are alcohols soluble/insoluble in water ?
Soluble
How could you distinguish an alcohol from another substance
It’s highly flammable and burn with a clean flame
What do alcohols react with to produce an ester ?
Carboxylate acids
What group does an alcohol have ?
Hydroxyl (-OH)
Name the alcohol with seven carbon atoms
Heptanol
What do carboxylate acids have in common
Graded physical properties such as me,ting and boiling points
What’s the functional group in a carboxylic acid ?
Carboxyl (-COOH)
What’s the ending of carboxylic acids
Oic
Name a carboxylic acid with 5 carbon atoms
Pentanoic acid
What is the chemical name for vinegar
Ethanoic acid
What is vinegar used for
Cleaner
Food preservative
Food flavouring
pH level of carboxylic acid
<7
What is the ester group
COO
How are esters formed
By a reaction between an alcohol and a carboxylic acid
Uses of esters
Food flavouring
Industrial solvents
Fragrances
Materials
How is the ester link formed
By the reaction of a carboxyl group and a hydroxyl group
What type of reaction is the burning of fuel
Exothermic
What does a substance react with when it burns
Oxygen
Give another word for burning
Combustion
What’s the energy change in an exothermic reaction
Chemical–> heat
What’s the energy change in an endothermic reaction
Heat–> chemical
What equation is uses to calculate the quantity of heat energy produced from a reaction
E = m X c X 🔼t
How can u distinguish a carboxylic acid from another substance
pH <7
How do you distinguish an alkene from another substance
It decolourises bromine solution
