Acids Flashcards
What does oxidising mean
Provides oxygen which allows other materials to burn more quickly
E.g liquid oxygen
What does harmful mean
Like toxic but not as dangerous
Eg cooper Sulfate
What does highly flammable mean
Catches fire easily
Petrol
What does irritant mean
Not corrosive but can cause reddening or blistering on the skin
Eg bleach
What does toxic mean
Can cause death either by swallowing breathing in or absorption through the skin eg hydrogen cyanide
What does corrosive mean
Attacks and destroys living tissues
Including eyes and skin
Eg concentrated sulfur in acid
What is an acid
A substance with a ph less than 7 Stomach acid Vinegar Acid rain Normal rain
What is an alkali
A substance with a ph greater than 7 A base that dissolves in water Washing up liquid Pancreatic juice Soap powder Ammonia Oven cleaner Caustic soda
What is a neutralisation reaction
Acid + base -> salt + water
When an acid and base react they form a salt and water and the products are neutral
What are the products of neutralisation reactions used for
Salts are used in fertilisers
They are used in fireworks as colouring agents
What is stomach acid
It is hcl in the stomach It helps with digestion Because the enzymes that work in the stomach work best in acidic conditions Helps to kill microbes and bacteria Can cause indigestion
How do indigestion tablets work
They contain bases such as calcium carbonate which can neutralise some of the stomach acid and stop indegestion
Acid + metal oxide
Salt and water
Acid + metal hydroxide
Salt + water
Hydrochloride acid + copper oxide
Copper chloride + water
Hydrochloric acid + sodium hydroxide
Sodium chloride and water
Sulfuric acid + zinc oxide
Zinc Sulfate + water
Sulfuric acid + calcium hydroxide
Calcium Sulfate + water
Nitric acid + magnesium oxide
Magnesium Nitrate + water
Nitric acid + potassium hydroxide
Potassium nitrate+ water
Formula for sulfuric acid
H2SO4
Formula for nitric acid
HNO3
What are the state symbols for a neutralisation reaction
Aq
Aq
Aq
L (water)
Acid + metal carbonate
Salt + water + carbon dioxide
Hydrochloric acid + sodium carbonate
Sodium chloride + water + carbon dioxide
2hcl + Na2CO3 ->2Nacl + H2O + CO2
Hydrochloric acid + calcium carbonate
Calcium chloride + water + carbon dioxide
What is electrolysis
Decomposition of a compound using electrical energy from a dc source
A liquid is required to carry the current called the electrolyte
Electricity is applied by two electrodes
What happens in the electrolysis of hydrochloric acid
Hcl is the electrolyte
It is split into hydrogen and chlorine gas
The gases bubble and can be collected in test tubes at the electrodes
Hydrogen at the cathode
Chlorine at the anode
What is the test for chlorine
Put damp blue litmus paper in the test tube and chlorine will bleach it and turn it white
What is the test for hydrogen
When a lit splint is put into hydrogen it creates a squeaky pop test
Happens in the electrolysis of sea water
Sodium chloride solution is decomposed
It creates chlorine gas
What are the uses of chlorine
Used to treat water supplies
Used in manufacture of bleach
Used to make polychloroethene (pvc)
What happens in the electrolysis of water
Hydrogen gas and oxygen gas are produced
What is the test for oxygen
If a glowing splint is put into the oxygen it will relight
