Acids and Alkalines
Steps of ionic bond?
1) Balanced symbol equation ( use state symbols) 2) Write down ions involved and state symbols 3) then anything that is aqueous, seperate into ions 4) cancel out the spectator ions, anything that is on both sides of the equation that are the same 5) you are left with a ionic equation
What is a base?
A base is a proton accepter A base is a substance that can react with acids and neutralise them. Bases are usually: metal oxides, such as copper oxide metal hydroxides, such as sodium hydroxide metal carbonates, such as calcium carbonate Ammonia too ( NH3)
What is neutralization reaction?
A chemical reaction happens if you mix together an acid and a base. The reaction is called neutralisation. A neutral solution is made if you add just the right amount of acid and base together. Neutralisation is an exothermic reaction, so the reaction mixture warms up during the reaction.
What colour does Phenolphthalein turn for acids and alkalines?
Acid: Colourless Alkaline: Pink
What colour does litmus paper turn for acids and alkalines?
Acid: RED Alkaline: BLUE
What colour does universal indicator turn for acids and alkalines?
Acid: Red Alkaline: Purple
What colour does methylorange turn for acids and alakalines?
Acid: Red Alkaline: Yellow/orange
What is an easy way to decide whether a substance is a acid, base or alkali
Alkalis - normally have OH ( Sodium hydroxide, NaOH) Base - Normally just has O ( Lithium oxide, Li2O) Acid - has an acid in the equation (Hydrogen nitrate, HNO3)
What is a alkaline?
An Alkali is a soluble base Any substance that produces OH- (hydroxide ions) in aqueous solution is called alkali.
What is an acid?
An acid is a proton donor
In an aqueous solution what is an acid the source of?
An acid is a source of hydrogen ions (H+) They are proton donors.
In an aqueous solution what is an alkali the source of?
An alkali is the source of hydroxide ions (OH-) is a proton donor and a base is a proton acceptor
What is the formula for Ethanolic acid?
CH3COOH
Hydrogen chloride (g)---->
Dissolved in water ----> Hydrochloric acid (aq)
What is the formula for sulphuric acid?
H2SO4
What is the formula for phosphric acid?
H3PO4
What is the formula for hydrochloric acid?
HCL
What is the formula for Nitric acid?
HN03
What is the experiment that turns an insoluble salt into a pure, dry sample of a soluble salt?
Heat acid (H2SO4) in a beaker. Add base (CuO) until no more copper oxide dissolves and stir with glass rod (This will neutralise all the acid). Filter the mixture using filter paper and funnel to remove any excess copper oxide. Heat the filtered solution (CuSO4) so a hot saturated solution forms. Allow the solution to cool so that hydrated crystals form. Remove the crystals by filtration and wash with distilled water which will remove any impurities. Dry by leaving in a warm place so the water evaporates.
Acid used + salt name ends in...
Hydrochloric acid ---> Chloride Nitric acid --------> Nitrate Sulphuric acid -----> Sulphate Ethanoic acid -------> ethanoate Phosphoric acid -----> phosphate
What is used to distinguish between acid and alkaline?
Litmus Phenolphthalein Methyl orange Universal indicator
Example of metal + acid ----> salt + hydrogen
Magnesium + HCl ----> Magnesium chloride + hydrogen
Example of Acid + metal oxide----> salt + water
Nitric acid + iron oxide ----> iron nitrate + water
Example of Acid + metal carbonate----> salt + water + C02
Phosphoric acid + calcium carbonate ----> calcium phosphate + water + C02
What is a precipitation reaction?
Precipitate/precipitation reaction- making something insoluble from 2 soluble When you mix the 2 soluble solutions together, the Clear soluble solutions together, forms a insoluble solid and a insoluble liquid.
Metal + Acid ----->
Salt + hydrogen
Acid + metal hydroxide ----->
Salt + water
Making insoluble salts
Silver nitrate and sodium chloride are both soluble. When their solutions are mixed together, soluble sodium nitrate and insoluble silver chloride are made: silver nitrate + sodium chloride → sodium nitrate + silver chloride AgNO3(aq) + NaCl(aq) → NaNO3(aq) + AgCl(s) The ionic equation for this process is as follows: Ag+(aq) + Cl-(aq) → AgCl(s)
Example of a precipitation reaction
Sodium carbonate + Magnesium sulphate ----> Sodium sulphate + magnesium carbonate Na2SO4 (aq) + MgSo4 (aq) ------> Na2SO4 (aq) + MgCO3 (s)
What are the solubility rules?
Sodium, potassium, ammonium - soluble Nitrates - soluble Common chlorides/bromides/iodides - Soluble (except Silver chloride, lead chloride) Common sulfates - Soluble (except lead, barium, and calcium sulfate) Common carbonates - Insoluble (except sodium, potassium and ammonium ones) Common hydroxide - Insoluble (except sodium, potassium and calcium ones)
Example of Acid + metal hydroxide ----> salt + water
Sulphuric acid + lithium hydroxide ----> lithium sulfate + water
What is the reaction between an acid and a base/ alkali?
The reaction is called neutralisation. (Acid-base reaction). H+(aq) + OH-(aq) → H2O(l) The reaction is seen as a proton transfer.The acid donates protons which are then accepted by the base. Acid - proton donor Base - proton accept-or
Difference between titration and precipitation reaction
Titration -> How much acid is used to neutrilise an alkaline Precipitation reactoin -> making an insoluble with 2 soluble solutions
What is solubility?
a solute's capability of being dissolved
When something is soluble, the state symbol is...
aq
metal oxides, metal hydroxides and ammonia can act as.....
bases
An acid isn't an acid until it is
dissolved in water
How to use the pH scale?
from 0-14, can be used to classify solutions as strongly acidic (0-3) weakly acidic (4-6) neutral (7) weakly alkaline (8-10) strongly alkaline (11-14)
What is a saturated solution?
max amount of solute, no longer dissolves
Alkalines _______ acids
neutralise
Acid + metal oxide ------>
salt + water
Acid + metal carbonate------->
salt + water + Carbon dioxide
What is the difference between strong and weak acid/alkali
strong acid/alkali - fully ionised when dissolved in water weak acid/alkali - only very slightly ionised when dissolved in water
