Acids & Bases Flashcards
What is a base?
A base is a substance that causes red litmus paper to turn blue and a pH of more than 7
What is an acid?
An acid is a substance that causes blue litmus paper to turn red and a pH of less than 7
Everyday acids
Lemon juice
Rain water
Vinegar
Lab acids
Hydrochloric acid
Sulphuric acid
Everyday bases
Tooth paste
Bleach
Indigestion tablets
Lab bases
Sodium hydroxide
Calcium hydroxide
Limewater
pH scale
Scale runs from 0-14 Indicates level of acidity or basicity Neutral 7 Acids >7 Bases < 7
Examples
Base baking soda
Acid lemon juice
Neutral water
What is an indicator?
An indicator is a chemical which shows, by means of a colour change, whether a substance is an acid or a base
Who does a neutralisation reaction occur?
An neutralisation reaction occurs when an acid and a base react together and neutralise each other to form a salt and water
What does the fire triangle include of?
Fuel, oxygen and heat. If any of these are removed a fire will not exist
What is a fossil fuel?
A fossil fuel is the remains of plants and animals that lived millions of years ago. Eg coal, petrol, oil
What are fossil fuels made of?
Fossil fuels are mainly made of 2 elements:
Hydrogen + carbon (hydrocarbons, eg. Natural gas (made of methane -> simplest hydrocarbon))
What do fossil fuels produce when they’re burned?
Water vapour and carbon dioxide
How is acid rain formed?
Carbon dioxide and sulphur dioxide dissolve in rain water
