Water Chemistry and Electrical Conductivity Database for ...
Properties of substances SG Chemistry, Topic 7. Conductivity of elements and compounds Standard...
-
Upload
lesley-ryan -
Category
Documents
-
view
214 -
download
0
Transcript of Properties of substances SG Chemistry, Topic 7. Conductivity of elements and compounds Standard...
Learning outcomes Success criteriaKnow which elements can conduct electricity. You can write a rule linking the type of element
to whether or not it can conduct electricity.
Given the name of an element, you can state whether or not it can conduct electricity.
Know which types of compound can conduct electricity.
Given the name of a compound, you can state whether it is made up of metal and non-metal elements or only non-metal elements.
You can write a rule linking the types of elements which make up a compound to whether or not it can conduct electricity.
Given the name of a compound and its state, you can state whether it can conduct electricity or not.
Gold
Lead
Sodium
Silicon
Carbon
Iodine
Hydrogen
Bromine
Mercury Sulphur Potassium Phosphorus
• What do the above substances have in common?– Elements
• Which of them conduct electricity?
Gold
Lead
Sodium
Silicon
Carbon
Iodine
Hydrogen
Bromine
Mercury Sulphur Potassium Phosphorus
• What do the above substances have in common?– Elements
• Which of them conduct electricity?– Metal elements and carbon (graphite)
• Does it make a difference what state the elements are in?– No
• Write a rule which summarises which elements can conduct electricity.– All metal elements can conduct
electricity (whether solid or liquid); non-metal elements do not conduct electricity in any state, with the exception of carbon (graphite).
True or false• All solid elements conduct electricity.• All liquid elements conduct electricity.• All metal elements conduct electricity.• No non-metal element conducts electricity.
• Solid oxygen conducts electricity.• Liquid oxygen conducts electricity.• Solid calcium conducts electricity.• Liquid calcium conducts electricity.• Solid carbon conducts electricity.
True or false• All solid elements conduct electricity.• All liquid elements conduct electricity.• All metal elements conduct electricity.• No non-metal element conducts electricity.
• Solid oxygen conducts electricity.• Liquid oxygen conducts electricity.• Solid calcium conducts electricity.• Liquid calcium conducts electricity.• Solid carbon conducts electricity.
Learning outcomes Success criteriaKnow which elements can conduct electricity. You can write a rule linking the type of element
to whether or not it can conduct electricity.
Given the name of an element, you can state whether or not it can conduct electricity.
Know which types of compound can conduct electricity.
Given the name of a compound, you can state whether it is made up of metal and non-metal elements or only non-metal elements.
You can write a rule linking the types of elements which make up a compound to whether or not it can conduct electricity.
Given the name of a compound and its state, you can state whether it can conduct electricity or not.
Practical – conductivity of compounds• If you were to investigate whether a compound can
conduct electricity or not, what equipment would you need?– Power pack / battery– Wires– Bulb
Results• Do compounds of metals/non-metals conduct
electricity when solid?– No
• Do compounds of metals/non-metals conduct electricity when liquid?– Yes
• Do compounds of metals/non-metals conduct electricity when dissolved?– Yes
Results• Do compounds of non-metals/non-metals conduct
electricity when solid?– No
• Do compounds of non-metals/non-metals conduct electricity when liquid?– No
• Do compounds of non-metals/non-metals conduct electricity when dissolved?– No
Do they conduct electricity?• Solid sodium chloride (salt)
• Solid glucose (C6H12O6)
• Liquid potassium iodide• Solid methane• Dissolved lithium nitrate• CaO(s)
• Al(OH)3(l)
• CsCl(aq)
• H2O2(l)
• C12H22O11(aq)
Do they conduct electricity?• Solid sodium chloride (salt)
• Solid glucose (C6H12O6)
• Liquid potassium iodide• Solid methane• Dissolved lithium nitrate• CaO(s)
• Al(OH)3(l)
• CsCl(aq)
• H2O2(l)
• C12H22O11(aq)
Learning outcomes Success criteriaKnow which elements can conduct electricity. You can write a rule linking the type of element
to whether or not it can conduct electricity.
Given the name of an element, you can state whether or not it can conduct electricity.
Know which types of compound can conduct electricity.
Given the name of a compound, you can state whether it is made up of metal and non-metal elements or only non-metal elements.
You can write a rule linking the types of elements which make up a compound to whether or not it can conduct electricity.
Given the name of a compound and its state, you can state whether it can conduct electricity or not.
Learning outcomes Success criteriaUnderstand what ions are. You can define the term ion.
You can describe two ways in which ions can be formed.
For elements 1-20, you can:– name their ions – draw symbols for their ions– draw shell diagrams of their ions– write electron arrangements for their ions
Learning outcomes Success criteriaUnderstand what ion migration is. You can explain the results of an ion migration
experiment, including:• specific colours• the direction which these move• ions• positive / negative• attract
Thought experiment: NaCl(aq)
Concentration (mol/l)
Current (A)
0.00.20.40.60.81.0
0.000.100.160.210.240.27
Thought experiment: C6H12O6(aq)
Concentration (mol/l)
Current (A)
0.00.20.40.60.81.0
0.000.000.000.000.000.00
Learning outcomes Success criteriaUnderstand what ion migration is. You can explain the results of an ion migration
experiment, including:• specific colours• the direction which these move• ions• positive / negative• attract
Learning outcomes Success criteriaUnderstand what electrolysis is. You can define the term “electrolysis”.
You can name the type of energy which changes a chemical during electrolysis.
From the name of a compound, you can– name the ion which will move to each electrode – state which ion gains electrons and which ion loses electrons– name the substance that will be produced at each electrode
Learning outcomes Success criteriaKnow what an electrolyte is. You can define the term “electrolyte”.
You can identify a substance as a electrolyte or not.
Understand why a d.c. supply must be used during electrolysis.
You can state what “d.c.” stands for.
You can state why a d.c. supply must be used.
Electrolysis
+
+
+
+
-
---
+ -
-
+
-+
++
+-
-
-
-
+ Copper
Chloride Why must a d.c. power supply be used?
What happens to the mass of each electrode?
Chemistry of electrolysis
Substance +ve electrode
Ion-electron equation
-ve electrode
Ion-electron equation
Aluminium iodide (molten)
Zinc bromide (solution)
Iron(II) chloride (solution)
Learning outcomes Success criteriaUnderstand what electrolysis is. You can define the term “electrolysis”.
You can name the type of energy which changes a chemical during electrolysis.
From the name of a compound, you can– name the ion which will move to each electrode – state which ion gains electrons and which ion loses electrons– name the substance that will be produced at each electrode
Learning outcomes Success criteriaKnow what an electrolyte is. You can define the term “electrolyte”.
You can identify a substance as a electrolyte or not.
Understand why a d.c. supply must be used during electrolysis.
You can state what “d.c.” stands for.
You can state why a d.c. supply must be used.
Learning outcomes Success criteriaUnderstand what an electric current is. You can describe what an electric current is in
terms of:– charged particles– movement
You can state the three examples of situations in which an electric current can flow.
Learning outcomes Success criteriaUnderstand how a current can flow in solutions or melts.
You can state the name of the charged particles which can flow in solutions/melts.
You can state what charge these particles can have.
You can state where these charged particles come from.
Conduction and molecules
Solid
Particles can’t move freely Liquid or solution
Particles can move freelyDoes not conduct – no charged particles Does not conduct
– no charged particles
Conduction and ions
+ -+
+-
-
+
+-
+
++
---
+
-+
-Solid
Particles can’t move freely Liquid or solution
Particles can move freelyDoes not conduct – ions can’t move freely Conducts
– ions can move freely
The rule• To conduct, charged particles must be
able to move freely.– In compounds, the charged particles are
ions.– The compound must be a liquid (melt) or
dissolved to conduct.
Learning outcomes Success criteriaUnderstand how a current flows in wires. You can state the name of the charged
particles which can flow in wires.
You can state what charge these particles have.
You can state where these charged particles come from.
Covalent bonding• What is a covalent bond?
• In what types of substance do we get covalent bonds?
• Examples?
• What do we know about substances with covalent bonding and their ability to conduct electricity?
Ionic bonding• In what types of substance do we get
ionic bonds?
• Examples?
• What do we know about substances with ionic bonding and their ability to conduct electricity?