Acids and Bases Flashcards
What is a base?
A base is a substance that causes red litmus paper to turn blue
What is an acid?
An acid is a substance that causes blue litmus paper to turn red.
Name three everyday acids
lemon juice (citric acid) rain water (carbonic acid) Vinegar
Name two lab acids
hydrochloric acid (HCl) Sulphuric acid (H2SO4)
Name three everyday bases
Toothpaste
Bleach
Indigestion tablets
Name three lab bases
Sodium hydroxide (NaOH) Calcium carbonate (CaCO3) Limewater Ca(OH)2
What is a pH scale? (what it is/ looks like)
A scale which runs from 0 -> 14
What does the pH scale do?
Indicates the level of acidity or basicity of a substance
What is the pH of neutral solutions?
7
What is the pH of acids?
less than 7
What pH do alkalis have?
greater than 7
What is water in terms of pH?
Neutral
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. e.g. litmus paper, universal indicator
Name two indicators
litmus paper
universal indicator
What is universal indicator paper used for?/how is it used
Universal indicator paper is used to measure the pH of a substance. The colour it changes to can be compared to a colour chart to find the pH
When does a neutralisation reaction occur?
A neutralisation reaction occurs when an acid and a base react together and neutralise each other to form a salt and water.
write out the changes that occur in a neutralisation reaction including the substances HCl (hydrochloric acid) and NaOH (sodium hydroxide)
Acid + Base —> Salt + water
HCl + NaOH —-> NaCl + H2O
Write out experiment “to neutralise a base by titration.
on it boss!
What do an acid and a carbonate react to form?
write out the formula.
salt, water and carbon dioxide
Acid + Carbonate = Salt + Water + Carbon dioxide
2HC + CaCO3 = CaCl2 + H2O + CO2
What is a fuel?
A fuel burns in oxygen to give out heat
write out experiment to investigate the reaction between zinc and hydrochloric acid and test for hydrogen
dattebayo
When a piece of zinc meets with hydrochloric acid what is formed?
write out the formula
hydrogen gas and zinc chloride
Zn + 2HCl = ZnCl2 + H2
Zinc + Hydrochloric acid = Zinc chloride + hydrogen
Write out the experiment to test for hydrogen.
Ahora
In the test for hydrogen when you bring a lit taper to the mouth of the test tube what happens?
a loud pop is heard
What is the diagram for fire called?
The fire triangle
What do you need to make fire?
fuel, oxygen and heat
What happens if a fire lacks oxygen, heat or fuel?
fire will not be made
What are fossil fuels? give three examples
the remains of plants and animals that lived millions of years ago e.g. coal, petrol, oil.
What can fossil fuels also be known as?
hydrocarbons
what are the two main elements that fossil fuels are made of
Hydrogen and Carbon
what is natural gas made of?
Methane CH4
What is the simplest hydrocarbon?
methane CH4
What do fossil fuels produce when they are burned?
Water vapour and carbon dioxide. they can also form sulphur dioxide.
What is formed when carbon dioxide and sulphur dioxide are are dissolved in rainwater.
Acid rain
water + carbon dioxide =
Water + sulphur dioxide =
carbonic acid
Sulphuric acid
What is carbonic acid made of?
carbon dioxide and water
What is sulphuric acid made of?
sulphur dioxide and water
Name two effects of acid rain
Kills fish and harms trees
Acid rain eats into buildings and statues, especially those made of limestone.
What is smog?
The name used for a mixture of smoke and fog.
How can it be prevented?
It can be prevented by using smokeless fuel.
Plastics are ___________ _________ materials.
man made
What are most plastics made of?
Most plastics are made from crude (unrefined) oil.
What is another name for simple hydrocarbons?
monomers
Where do monomers come from?
crude oil
What do monomers react together to form?
polymers
How are polymers formed?
when monomers react together
what are polymers used to make?
plastic
what are plastics made of?
polymers
What is PVC?
strong plastic
name two forms of PVC?
can be flexible or rigid
name two things madeof flexible PVC
Raincoats and shower curtains
name three types of plastic
PVC
Polythene
Nylon
describe polythene using three words
strong cheap and flexible
name two things polythene is used to make
plastic bags and lunch boxes
Name one feature of nylon
can be spun into fibres.
name two things nylon is used to make
tights, carpets and brushes
plastics do not…
degrade or break down easily
plastics are ______________.
non biodegradable
what does non biodegradable mean?
they cannot be broken down by living things
what do many plastics release when burned
release toxic fumes
when do plastics often release toxic fumes?
when they are burned
