Year 8 Term 1 - Acids, Alkalis and Neutralisationa Flashcards
Acids must be dissolved in water. What was the solid acid you dissolved in this topic?
Citric acid
More Acidic: 100g Hyrdochloric acid in 1L water / 1g acid in 1L water
100g in 1L
100 times more
Where can you find hydrochloric acid?
In the stomach
Where is sulphuric acid used?
Car batteries
Where is nitric acid used?
Fertilisers
Where can you find ethanoic acid?
In vinegar
Where can you find citric acid?
In citrus fruits such as oranges and lemons
Where can you find carbonic acid?
Fizzy drinks
What’s the highest pH value on the scale?
14
What substance might have the pH value 14?
Sodium hydroxide (oven cleaners)
What do you use calcium hydroxide for? (Lime)
Neutralising soil with too much acid
What do you use magnesium hydroxide for?
Indigestion remedies
What do you use sodium hydroxide for?
Oven cleaners
What do you use ammonia for?
Cleaning silver and brass
What natural substances can be used to make indicators?
Red cabbage and rhubarb
What colour was the red cabbage indicator in acid and alkali?
Acid: pink/red
Alkali: green
4 names of indicators
Methyl orange, brothymol blue, phenolphthalein and litmus
Methyl orange colours in acid and alkali
Red in acid and yellow in alkali
Colour of Brothymol blue in acid and alkali
Yellow/orange in acid and green in alkali
Phenolphthalein in acid and alkali
Colourless in acid and pink in alkali
Litmus in acid and alkali
Red in acid and blue in alkali
What pH number is neutral?
7
A pH with less than 7 is..
Acidic
A pH with more than 7 is…
Alkaline
0-2 is what colour in universal indicator
Red
3-4 is what colour in universal indicator
Orange
5-6 is what colour in universal indicator
Yellow
7 is what colour in universal indicator
Green
8-9 is what colour in universal indicator
Blue/green
10-11 is what colour in universal indicator
Blue
12-14 is what colour in universal indicator
Purple
A pH of 0-3 means the solution is..
Strongly acidic
A pH of 4-6 means the solution is..
Weakly acidic
A pH of 8-10 means the solution is..
Weakly alkaline
A pH of 11-14 means the solution is..
Strongly alkaline
Why are pH meters more accurate?
They can record the pH to 1 d.p. and don’t rely on people interpreting the measurement
Any metal oxide that cannot dissolve in water is called a..
Base
An example of a metal oxide is..
Copper oxide
A metal oxide that can dissolve in water is called an
Alkali but also a base at the same time
An example of a metal hydroxide is
Sodium hydroxide and calcium hydroxide
An example of an acid and base neutralising
Hydrochloric acid + potassium/sodium hydroxide = neutral solution
Acid + base = salt. This is:
Neutralisation
If an acidic solution has universal indicator in it and is neutralised what colours will the solution go through before it becomes neutral ?
Red to orange to yellow to green
Acid + base =
Salt + water
In indigestion treatment ……. Neutralises ………. In the stomach
Magnesium hydroxide, hydrochloric acid
Treating bee stings could use ……. To neutralise the sting
Soap - a weak alkali or base
Treating wasp stings could use … to neutralise the sting
Vinegar - a weak acid
Treating nettle stings can use … to neutralise the sting
Doc leaves/ soap - a weak acid
Treating acid soil could use … to neutralise the soil
Calcium hydroxide (lime)
What happens to the acid as it dissolved in water in under acid-style reactions?
It splits apart
What happens if you mix citric acid and sodium hydrogencarbonate?
Nothing
What 3 things happen when you mix citric acid and sodium hydrogencarbomate and add water?
It fizzes, it cools down and it gives a colourless solution