Acid and alkali
Give one example of a common acid found in the kitchen.
Vinegar – contains ethanoic acid, or lemon juice – contains citric acid
Which gas is produced when an acid reacts with a metal?
Hydrogen gas
What is a neutralisation
Is a bee sting acidic or alkaline?
Acidic
What colour does universal indicator turn in a strong acid?
Red
State one property of an alkali.
turns red litmus blue, pH > 7, can neutralise acids
Which gas is produced when an acid reacts with a carbonate?
Carbon dioxide
Name one real-life use of neutralisation.
Treating acidic soil with lime, stomach antacids, neutralising acidic industrial waste
Is a wasp sting acidic or alkaline?
Alkaline
What colour does universal indicator turn in a strong alkali?
Purple
A cleaner has pH 12. Is it an acid or alkali, and is it strong or weak?
Strong alkali
Describe the test for hydrogen gas and its result.
Put a lit splint near the gas; it produces a squeaky pop
Farmers often add lime to their fields. Explain why this is done.
(Lime is calcium carbonate)
To neutralise acidic soil so crops grow better
Suggest a household item to help treat a bee sting.
Baking soda
Which pH range shows a strong alkali?
pH 11-14
Explain why concentrated acids and alkalis are both dangerous, even though they are opposite in pH.
Both can cause chemical burns and corrosive.
Describe the test for carbon dioxide gas and its result.
Bubble the gas through limewater; it turns milky/cloudy
A factory discharges acidic water into a river. Propose a safe, cost-effective neutralisation method and explain the science.
Add calcium hydroxide/lime; the alkali neutralises the acid,
Suggest a household item to help treat a wasp sting.
Vinegar or lemon juice
Which pH range shows a strong acid?
pH 0-3