C3a- Organic Chemistry Flashcards
The alkali metals have …… density
Low
Why was Dmitri Mendleevs’ periodic table better?
He left gaps
Predicted properties of undiscovered elements
How do you remove temporary hardness?
Boiling to decompose to calcium carbonate (limescale)
How do ion exchange columns work?
Ca and Mg ions are exchanged for sodium ions
If you lower the pressure on one side of a reversible reaction, the reaction which produces ……. volume will be favoured.
More
The first good effort of the periodic table was…
Why was it criticised?(3)
Newlands’ Law of Octaves
Every 8th element had similar properties
No gaps
Mixed up metals and non metals
Groups contained elements that didn’t have similar properties
When alkali metals react with water, ……… is produced. Aswell has ……….. that dissolve in water to give alkaline solutions.
Hydrogen gas
Hydroxides
What is temporary hardness in water cause by?
Hydrogencarbonate (HCO3)
Positives of soft water?
Lathers soap
No limescale
Both types of water hardness can be removed by adding…. Or ….
Washing soda (sodium carbonate) > CaCO3 Ion exchange columns
If you lower the pressure on one side of a reversible reaction, the reaction which produces ……. volume will be favoured.
More
Hardness of water is caused by…
Ca and Mg ions
Reversible reactions will reach …………
Equilibrium
Positives of hard water?
Ca ions are good for healthy bones and teeth
Studies show less risk of heart disease
What is permanent hardness in water caused by?
Calcium sulfate
In a reversible reaction, if you reduce the temperature the …………… reaction will be favoured
Exothermic
What does the haber process produce?
Ammonia
In the alkali metals, as you go down the group they become …….. reactive and have ……… melting and boiling points.
More reactive
Lower melting and boiling points
Negatives of hard water?
When heated > scale
Makes scum with soap
Transition metals make ………. compounds
Colourful
What are the 4 stages of water treatment and what do the stages do?
Mesh screen- remove big parts eg twigs
Chemicals added to make solids and microbes stick together and fall to bottom
Filtration through gravel beds removes solids
Water chlorinated to kill off any harmful microbes left
Why do some people not agree with fluoride and chlorine being added to water?
Chlorine- cancer- reacts with substances in body
Fluoride-cancer and bone problems
The modern periodic table is based on …………… ………..
Electronic structure
If you raise the pressure on one side of a reversible reaction, the reaction which produces ……. volume will be favoured.
Less
More ………… halogens will ………….. less reactive ones
Reactive
Displace
What are the properties of transition metals? (4)
Good conductors of heat and electricity Dense strong shiny Less reactive than g1 Stronger than g1 Higher MP/BP than g1
Where is hydrogen obtained from for the Haber process?
Natural gas
Other sources such as crude oil
In group 7 (halogens) as you go down the group, the elements get ……. reactive and have a ………. melting and boiling point.
Less
Higher
The very early periodic table was based on ………… …….
Atomic mass
Equilibrium means …
The amounts of reactants and products will reach a certain balance and stay there. Overall effect is nil because forward and reverse reactions cancel each other out.
In a reversible reaction, if you raise the temperature the …………… reaction will be favoured
Endothermic
The halogens are all non-metals with ………… ……….
Coloured vapours
What are the industrial conditions for the Haber process?
450 degrees C
200 atm pressure
Iron catalyst
What is the alcohol functional group?
-OH
What is the functional group for carboxylic acids?
-COOH
What do carboxylic acids names end in?
-anoic acid
Why do carboxylic acids dissolve in water to produce weak acidic solutions?
As they do not ionise completely (not many H+ ions are released)
What is the functional group for esters?
-COO
How are esters formed?
Alcohol + carboxylic acid -> ester + water
How does washing soda (sodium carbonate) remove hardness of water?
The added carbonate ions react with Ca and Mg to make an insoluble precipitate of calcium carbonate and magnesium carbonate.
The first three alcohols dissolve completely in water to form ……….. solutions
Neutral
Give two uses how alcohols are used as solvents
Perfumes/aftershaves
Methylated spirits- used to clean paint brushes
Name some common carboxylic acids
Ethanoic acid- vinegar
Citric acid- fizzy drinks
How can ethanoic acid be made?
Oxidising ethanol
Carboxylic acids are used in industry to make …….. and ……….
Soaps
Esters
Carboxylic acids with longer chains of carbon atoms are used to make …….. and …………..
Soaps
Detergents
Ethanoic acid is a good solvent for organic molecules. Why isn’t it hoses as a solvent?
It makes the solution acidic
Esters are formed from …
What catalyst is used?
An alcohol and carboxylic acid
An acid catalyst
Ethanoic acid + ethanol –> ….
Ethyl ethanoate + water
In esters the written order is…
Alcohol then acid
In esters the drawn order is
Acid then alcohol
What affe the properties of esters?
Sweet smelling
Volatile- flammable
Do not mix well with water
Mix well with alcohols and other organic solvents
What are the dangers of esters?(3)
Inhaling = irritates mucous membranes in nose and mouth
Flammable
Some are toxic
Name some uses of esters(4)
Perfumes
Flavourings/aromas
Ointments (deep heat)
Solvents for paint, ink, glue, nail varnish remover
What can you use titration a to find out?
How much acid is needed to neutralise an alkali (or vice versa)
Name two indicators that are used in titration
Phenolphthalein
Methyl orange
Why are the chosen indicators used in titration and not universal indicator?
As you want a definite colour change
In titration, the point at which the acid and alkali have reacted completely is called the …… ………..
End point
Outline the stages of titration
Known volume in conical flask using pipette
Solution of unknown into burette
Slowly add unknown into known
When indicator changes colour (end point) read how much unknown has been added to the known (from bottom of meniscus on scale)
Repeat process
Energy is ………… when bonds are broken
Supplied
Energy is ………… when bonds form
Released
Bond breaking is an ………….. process
Endothermic (as energy is taken in)
Bond formation is an …………. process
Exothermic
Fuel energy is calculated using …………
Calorimetry
For the Haber process, where is nitrogen obtained from?
Easily obtained from the air (which is 78% nitrogen)
