Acids and alkalis Flashcards
How to measure pH
Litmus paper and universal indicator
What colour does red litmus paper turn when reacting with an acid
Red
What colour does red litmus paper turn when reacting with an alkali
Blue
What colour does litmus paper turn when reacting with a neutral
It stays the same colour
What colour does blue litmus paper turn when reacting with an acid
Red
What colour does blue litmus paper turn when reacting with an alkali
Blue
What order does the colour pH scale go
Red, orange, yellow, green, blue and purple
What is a pestle and mortar
The mortar is the bowl and the pestle is the stick you crush the items inside the mortar with
What is a solvent
The liquid an item(solute) is being dissolved in
What is a solute
Something that dissolves in a liquid (solvent)
What is neutralisation?
When an acid reacts with an alkali/ base that cancels it out. The pH gets closer to 7.
How to neutralise a bee sting
Bee stings are acidic so adding an alkaline/ base would bring the pH closer to 7.
What is the difference between a base and an alkali
An alkali dissolves in water( soluble) but a base does not (insoluble).
How does neutralisation solve indigestion
Our stomachs have hydrochloric acid and too much can cause indigestion so antacid tablets contain bases to neutralise the extra acid but not too much to an extent that the stomach pH is too close to neutral.
How does neutralisation solve the soil for crops
Plants can’t grow on acidic soil so you can add bases to make the soil less acidic, where crops can grow.
How does neutralisation solve brushing teeth
Incorporating fluoride ,an alkali, into the tooth enamel makes your teeth more resistant to acids and plaque, also acidic.
How does neutralisation solve acidic lakes
Powdered limestone is alkaline so adding it to acidic lakes would neutralise the pH. This is called liming but it is expensive and temporary.
In the indigestion remedy tablet investigation, what would you use to represent the acid in the stomach
Hydrochloric acid
How can you measure reactivity in the indigestion tablet investigation
If it fizzes for the longest and turns green with drops from the universal indicator it works very well.
How to tell whether another metal has a higher reactivity than the other
If one metal displaces another metal it means it has a higher reactivity. Displacement is replacing a less reactive metal with a more reactive one in a compound.
Magnesium + sulfuric acid =?
Magnesium sulfate + hydrogen
Chemical formula for Sodium
Na
Chemical formula for hydrochloric acid
HCl
Chemical formula for hydrogen
H2
Chemical formula for sulfuric acid
H2SO4
Chemical formula for nitric acid
HNO3
Chemical formula for copper
Cu
Chemical formula for calcium
Ca
Chemical formula for nitrate
NO3
Chemical formula for sulfate
SO2-4
Chemical formula for vinegar
C2H4O2
Chemical formula for carbon
C
Chemical formula for helium
He
Chemical formula for gold
Au
Chemical formula for silver
Ag
Chemical formula for nitrogen
N2
Chemical formula for tin
An
Chemical formula for magnesium
Mg
Chemical formula for zinc
Zn
Chemical formula for sulfur
S8
Chemical formula for iron
Fe
What does an acid and base make
Salt and water
What does metal and acid make
Salt and hydrogen
What does acid and metal carbonate make
Salt + carbon dioxide + water
What does sulphuric acid react to
Sulfate
What does hydrochloric acid react to
Chlorides
What does nitric acid react to
Nitrates
Properties of carbon
Insoluble, inert and at high temperatures reacts with oxygen to form carbon monoxide/dioxide
Properties of calcium
Used to build strong bones and is a silvery white metal
Properties of neon
Second lightest gas that is odourless and colourless and used in high voltage indicators like lights
Properties of sulfur
Insoluble, pale yellow, odourless, tasteless, poor conductor and used in car batteries
Properties of copper
Malleable, ductile, good conductor and used in coins/ jewellery
What does malleable mean
Can be compressed to change shape
What does ductile mean
Able to be made into a thin wire
Properties of helium
Lightest noble gas, inert, colourless, odourless and used in airbags in cars
Properties of iron
Shiny, ductile, malleable, silver grey colour and used in appliances
Inert meaning
Chemically unreactive
Properties of gold
Used in jewellery and most ductile, malleable of all metals and is expensive because it has a low reactivity
Properties of sodium
Very reactive, good conductor, low density, malleable and ductile and boiling point is 98 degrees
Properties of nitrogen
Colourless, odourless, tasteless and most plentiful element in the atmosphere and is used in explosives
How can you tell something is a metal
Shiny, solid at room temp (apart from mercury) malleable, ductile and have a high melting point and are good conductors (except graphite)
What do you add when a metal reacts with oxygen
Oxide
Are non metal oxides alkaline or acidic
Acidic
How to describe non metal oxides
Dissolve in water to form acidic solutions
How to describe metal oxides
Dissolve in water to produce alkaline solutions
What is the pop test
If you put hydrogen in a test tube and put a lighted match above it, it should make a pop sound.
How does iron react to hydrochloric acid
Air bubbles
How does magnesium react to hydrochloric acid
Fizzes
How does zinc react to hydrochloric acid
Air bubbles
How does copper react to hydrochloric acid
No reaction because it is less reactive
Reactivity series of metals
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Hydrogen
Copper
Silver
Gold
Platinum
What happens to the displaced metal in a reaction
It is left pure and uncombined.
What metal is used to displace valuable copper from a solution in industry
Iron