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Conduction Of Electricity. Elements. hydrogen sodium neon sulphur magnesium gold carbon iodine. Conduction Of Electricity. Solids. calcium sodium chloride sugar silver copper sulphate potassium bromide carbon. Covalent Compounds. ice sugar solution hexane sugar glucose
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Conduction Of Electricity Elements hydrogen sodium neon sulphur magnesium gold carbon iodine
Conduction Of Electricity Solids calcium sodium chloride sugar silver copper sulphate potassium bromide carbon
Covalent Compounds ice sugar solution hexane sugar glucose pure water ammonia solution
Ionic Compounds sodium chloride lithium bromide solution magnesium sulphate molten sodium chloride aluminium oxide copper sulphate solution
Electric Current electrons copper chloride solution ions ionic bonding
Ionic Substances This diagram shows how positive sodium ions and negative chloride ions are held together. - + + - + - + - + + - - + - - + + This arrangement is known as an ionic lattice.
- + + - + - + - + + - - + - - + + Ionic Substances When an ionic solid dissolves in water the lattice breaks down and the ions are free to move.
Electrolysis Electricity flows through the solution because the ions are free to carry the charge. Copper chloride is known as an electrolyte. Direct current (dc) must be used. copper chloride solution
Electrolysis The copper chloride is broken down when electricity passes through the solution (or melt). Show animation copper chloride solution
Electrolysis positive ions ______>negative electrode negative ions ______> positive electrode Only with ionic compounds – ions carry charge CuCl2 (aq) copper ions ______> negative electrode, copper deposited chloride ions ______> positive electrode, chlorine evolved
Electrolysis Cu2+ (aq) + 2e- ________> Cu(s) 2 Cl-(aq) ________> Cl2(g) + 2e-
Electrolysis NaCl (l) sodium ions ______> negative electrode, sodium deposited chloride ions ______> positive electrode, chlorine evolved Cl-(l) ________> Cl2(g) + 2e- 2 Na+ (l) + 2e- ________> 2Na(s) 2
Electrolysis H2O (l) hydrogen ions ______> hydrogen evolved oxide ions _____> oxygen evolved H+ (aq) + 2e- ________> H2 (g) 2 2O2- (aq) ________> O2(g) + 4e-
Complex Ions + ammonium nitrate permanganate sulphate carbonate NH4 NO3 MnO4 SO4 CO3 Data booklet page 4 - - 2- 2- Valency is the same as the number of charges.
Writing Formulae Using Valency (water) hydrogen oxide symbol valency swop divide formula H O 1 2 H2O 2 1
Writing Ionic Formulae copper (II) nitrate - symbol valency swop divide formula Cu2+ 2 1 Cu2+(NO3 )2 NO3 1 2 -
Writing Ionic Formulae ammonium sulphate 2- + symbol valency swop divide formula NH4 1 2 (NH4 )2SO4 SO4 2 1 + 2-
Writing Ionic Formulae aluminium hydroxide 3+ - symbol valency swop divide formula Al 3 1 Al(OH )3 OH 1 3 3+ -
Writing Ionic Formulae iron (II) carbonate 2+ 2- symbol valency swop divide formula Fe 2 2 1 FeCO3 CO3 2 2 1 2+ 2-
Writing Ionic Formulae Using exactly the same method work out the formula of the following compounds. potassium permangante mercury (II) nitrate copper sulphate ammonium nitrate sodium carbonate ammonium carbonate iron (III) sulphate ammonium phosphate mercury (I) nitrate copper (I) hydroxide
Solubility Ionic solids dissolve in water, a polar solvent. Covalent solids do not dissolve in water. Covalent solids dissolve in white spirit, a non-polar solvent. Ionic solids do not dissolve in white spirit.
Solid,Liquid or Gas? Data Booklet page 6.
Solid,Liquid or Gas? Ionic compounds are solid at room temperature because the ionic bonds holding the ions together are very strong. Most covalent compounds exist as liquids and gases because the bonding is weak.
Covalent Network Diamond Covalent network - hardest natural substance - very high melting point Graphite, silicon dioxide are also covalent network solids. Also have very high melting points.