Neutralisation Flashcards
What type of alkali is soluble in water
Hydroxide
Test for hydrogen
Place a lighted splint in a test tube containing the gas. If the gas is hydrogen, there will be a squeaky pop.
What colour is litmus paper in acid and alkali
Red in acid
Blue in alkali
What colour is phenolphthalein in acidic, alkaline or neutral
Acid- light red
Alkali- dark pink
Neutral- colourless
What colour is methyl orange in acidic, alkaline and neutral substances
Acid- red
Alkali- orange
Neutral- yellow
What are the limitations of using phenolphthalein as an indicator
Changes colour in a narrow ph range making it unsuitable for detecting weak acids or bases.
Colour also fades especially in light
What are the limitations of using methyl orange as an indicator
methyl orange would be yellow in any solution with a pH greater than 4.4. It couldn’t distinguish between a weak acid with a pH of 5 or a strong alkali with a pH of 14.
What are the limitations of using litmus paper as an indicator
It’s not an accurate indicator of ph
Describe the difference between an alkali and a base
Bases are insoluble in water. On the other hand, alkali produces ions when dissolving in water
Name some common acids and describe their properties
Acids are sour in taste
Acid reacts with metal to form hydrogen gas.
Blue litmus turns red in acid.
Vinegar (contains acetic acid).
Lemon Juice (contains citric acid).
Vitamin C
Name some common alkali and describe their properties
turn litmus paper from red to blue;
they react with acids to yield neutral salts;
and they are caustic and in concentrated form are corrosive to organic tissues.
Sodium hydroxide
Calcium hydroxide
Potassium hydroxide
Ammonia
Sodium
Calcium carbonate
Give examples of neutralisation reactions in action in real life
Adding lime to acidic soil
Vinegar on a wasp sting
Bicarbonate of soda on a bee sting
