c4 Flashcards
How can you measure the pH of a solution?
Universal indicator or a pH probe or pH meter
What do acids and bases produce/do?
neutralise each other by producing salt and water
What do acids produce in water?
protons
What do strong acids do in water?
ionise completely (dissociate to release protons)
What do weak acids do in water?
Not fully ionise (small proportion dissociate)
Why are weak acids reversible?
Only a few acid particles have been released
Why are strong acids more reactive?
concentration of protons are higher so the r of r is faster
What is pH a measure of?
The concentration of hydrogen ions
How to measure the concentration of hydrogen ions?
For every decreases of 1 on the pH scale the concentration increases by a factor of 10.
What does acid strength tell you?
What proportion of acid molecules ionise in water
What does concentration tel you?
How much acid there is in a certain volume of water
What are metal oxides and metal hydroxides
(salt + water)
What do acids and metal carbonates produce?
carbon dioxide and bases (salt and water)
How is metals reactivity determined?
how easily they loose electrons ( forming positive ions)
How are positive ions formed?
When metals react with water or an acid (So the further a metal is in the reactivity series the more easily it reacts with a water or acid
What is the reactivity series?
Potassium Sodium Lithium Calcium Magnesium Carbon Zinc iron Hydrogen Copper
How do you find the speed of the reaction?
The rate at which bubbles are given off
why do some metals react explosively?
very reactive
What is produced when metals react with water?
metal hydroxide and hydrogen
What is oxidation?
GAIN OF ELECTRONS (common metals react with oxygen)
What is a reduction reaction?
LOSS OF ELECTRONS (separating a metal from its oxide)
What metals have to be extracted using electrolysis?
Metals higher than carbon in the reactivity series because carbon can only take oxygen away from meals which are less reactive than itself
What is REDOX?
reduction & oxidation happening at the same time.
What is the displacement rule?
A MORE REACTIVE metal will displace a LESS REACTIVE metal from its compound.
What type of ion always gains electrons and is reduced in displacement reactions?
A metal ion
What do ionic equations concentrate on?
The substances that are oxidised or reduced
