Chemistry (C4) Flashcards
\What is an acid?
A substance that produces H+ ions in aqueous solutions (dissolved in water)
Has a pH of less than 7
What is an alkali?
A substance that produces hydroxide ions, OH-(aq), when dissolved in water
A soluble base
Has a pH higher than 7
What is a base?
A insoluble substance that reacts with an acid to neutralize it and produce a salt.
Give the pH range of an acid
pH 0-6
Give the pH range of an alkali
pH 8-14
Give the pH of a neutral solution
pH 7
What is the pH scale?
A measure if how acidic or alkaline a solution is
What does pH mean?
Potential hydrogen
The greater the concentration of H+ ions in
solution, the ____________ the pH.
Lower
As the pH of a solution increases by 1, the concentration of hydrogen ions _________ by a factor of _____
Decreases, 10
What are universal indicators?
Chemicals that change colour to tell you whether a solution is acidic or basic
What is a strong acid?
Fully ionises in an aqueous solution to form H+ ions
What is a weak acid?
Partially ionises in aqueous solutions to form H+ ions
What does ‘⇌’ mean in a reaction?
Partially ionises
What does ‘→’ mean in a reaction?
Fully ionises
What is a concentrated acid?
A concentrated acid has a large amount of H+ ions volume of water
What is a dilute acid?
A dilute acid has a small amount of H+ ions in a given volume of water
What is neutralisation?
A chemical reaction between an acid and alkali to form a neutral solution
Acid + Metal hydroxide → ? + ?
Salt + Water
Acid + Metal Oxide → ? + ?
Salt + Water
Name the salt formed when calcium hydroxide with nitric acid
Calcium nitrate
Name the products formed when a
metal carbonate reacts with an acid.
Salt + water + carbon dioxide
Name the products formed when magnesium carbonate reacts with hydrochloric acid
Magnesium Chloride + water + carbon dioxide
What are titrations ?
A very accurate experimental technique which finds the unknown concentration of a solution
What are concordant results?
Results which are very close to each other
What is the name of the reaction where a substance gains oxygen?
Oxidation reaction
Metal + Oxygen → ?
Metal Oxide
Copper + Oxygen → ? + ?
Copper oxide
Describe a method to make pure, dry crystals from a metal oxide and dilute acid?
-Measure out acid
-pour acid into a beaker
-add an excess amount of metal oxide in the beaker
-stir and mix reactants
-set up a conical flask with a funnel and filter paper
-Add in the mixture for filtration
-The acid will filter through and become filtrate
-The metal oxide will stay in filter paper as residue
-Add the filtrate into an evaporation basin
-Heat up the filtrate with a Bunsen burner
Then leave the crystals to cool and dry
Observations of potassium reacting with oxygen
Lilac flame
Observations of sodium reacting with oxygen
Orange flame
Observations of Lithium reacting with oxygen
Red flame
Metal + Acid → ? + ?
Salt and hydrogen
Observations of metal reacting with acid
Metal dissolves
Gas produced
Fizzing
Observations of Potassium reacting with acid
Explosive
Vigorous bubbles
Observations of Sodium reacting with acid
Explosive
Vigorous bubbles
Observations of Lithium reacting with acid
Explosive
Vigorous bubbles
Observations of Calcium reacting with acid
Fizzes/warm
Observations of Magnesium reacting with acid
Fizzes/warm
Observations of Zinc reacting with acid
Fizzes slowly
Observations of Iron reacting with acid
Fizzes slowly
Observations of copper reacting with acid
No reaction
Metal + Water → ? + ?
Metal hydroxide + hydrogen
Observations of metal reacting with water
Metal dissolves
temperature increase
Fizzing
Lithium + Water → ? + ?
Lithium hydroxide + hydrogen
Name the reactivity series
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Hydrogen
Copper
Silver
Gold
Platinum
Observations of Potassium reacting with water
Fizzes
Melts
Floats
Moves on the surface of water
lilac flame
Observations of sodium reacting with water
Fizzes
Melts
Floats
Moves on surface of water
sometimes a yellow orange flame
Observations of Lithium reacting with water
Fizzes
Floats
Moves on the surface of water
Observations of Calcium reacting with water
Fizzes
White solid forms
Warm
Observations of Magnesium reacting with water
Very slow
Observations of zinc reacting with water
No reaction
Observations of Iron reacting with water
No reaction
Observations of Copper reacting with water
No reaction
What is a displacement reaction?
When a more reactive metal displaces a less reactive metal from its compound
Iron + Copper sulfate → ? + ?
Iron sulfate + Copper
What is an ore?
An ore is a rock containing a metal compound from which a metal can be extracted for profit
Which metals don’t use an extraction method?
Silver
Gold
Platinum
Which metals are extracted from their ores chemically by reduction using carbon?
Zinc
Iron
Tin
Lead
Copper
Which metals are extracted using electrolysis?
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Whats does OIL RIG stand for?
Oxidation
Is
Loss of electrons
Reduction
Is
Gain of electrons
What is a redox reaction?
Where REDuction and OXidation take place at the same time
What is Electrolysis?
Electrolysis is using electricity to break down electrolytes to form elements
What does electrolysis mean?
Splitting up with electricity
What is an electrolyte?
A liquid or solution that can conduct electricity
What is an electrode?
A solid that conducts electricity
What is the positive electrode called?
Anode
What is the negative electrode called?
Cathode
What happens in electrolysis?
An electric current is passed through an electrolyte
Ions begin to move to the electrodes where they react
Positive ions move towards the cathode and gain electrons
Negative ions move towards the anode and lose electrons
Creates a flow of charge
As ions gain or lose electrons they form uncharged elements
What is a positive ion called?
Cation
What is the negative ion called?
Anion
Can an ionic solid be electrolysed?
No because ions are in fixed positions and cant move
When can ionic compounds conduct electricity?
Ionic compounds can conduct electricity when molten or dissolved as the ions are free to move
Which non metals always win?
Fluorine
Chlorine
Bromine
Iodine
Astatine
(Halogens)
Which metals always win?
Copper
Silver
Gold
Tin
Lead
What does the charges on elements symbolise?
Oxidation states
What is reduction?
When a substance loses oxygen
What is pH probe?
A device used to measure the acidity or alkalinity of a substance
What does PANIC stand for?
Positive
Anode
Negative
Is
Cathode
Which electrode will the positive ion go to?
Cathode
Which electrode will the negative ion go to?
Anode
Describe the structure of diamond
Giant covalent lattice
Tetrahedral structure/each carbon atom is covalently bonded to four other atoms
Give 6 properties of transition metals
Hard
High density
High melting boiling points
Form coloured compounds
Low reactivity
Form different charged ions
How is ore extracted?
Ore is mined and then processed to separate the metal compound
