- Slides: 20
1. Neutron A. The number of protons in an atom. 2. Proton B. Hold the electrons around the nucleus. 3. Electron C. The number of protons plus neutrons in an atom. 4. Nucleus D. Represented by symbols in the periodic table. 5. Atomic number E. Negatively charged particle that moves around the nucleus. 6. Mass number F. Positively charged particle found in the nucleus. 7. Energy shell G. The middle of the atom where protons and neutrons are found. 8. Element H. Particle found in the nucleus that has no charge.
Ionic bonding(C 1. 1. 3 a) I can recall how compounds are made. �Compound �Atom �Ion I can describe why sodium chloride is formed from its ions. �Electron �Transfer �Charge I can explain what happens to the electrons during ionic bonding. I can list the properties of ionic compounds. �Ionic �Bonding �Sodium Chloride
Ions • An ion is an atom which has gained or lost electrons and so has become charged. • 1. 2. • Draw the electronic configuration of: Sodium atom Chlorine atom We will then draw sodium and chlorine ions.
Metals • When metal ions form ions they lose electrons. • Metal ions always have a positive charge.
Non-metals • When non-metals atoms form ions they gain electrons. • Non-metal ions always have a negative charge.
Ions • 1. 2. 3. Draw: A lithium ion and state its charge. A fluorine ion and state its charge. An oxygen ion and state its charge.
Sodium chloride • https: //www. youtube. com/watch? v=zpa. HPXVR 8 WU
Sodium chloride • Sodium and chlorine bond together to form sodium chloride. • Bonding between a metal and a non - metal is ionic bonding.
Magnesium and oxygen • Magnesium ions have the formula Mg 2+, and oxide ions have the formula O 2 -. • The compound magnesium oxide is held together by strong forces of attraction between the oppositely charged ions.
Feeling brave? • Have a go at Calcium chloride
Calcium and chlorine • Calcium ions have the formula Ca 2+, and chloride ions have the formula Cl-. • You need to show two chloride ions because two chloride ions are needed to balance the charge on a calcium ion.
Questions 1. Explain why magnesium oxide has the formula Mg. O. 2. Explain why calcium chloride has the formula Ca. Cl 2. 3. Predict the formula of the ionic compound magnesium chloride.
Properties of ionic compounds • Metal and non-metal. • Metal ions lose electrons to become positively charged. • Non-metal ions gain electrons to become negatively charged.
Giant structure • Consist of many ions which form a giant structure, with strong electrostatic forces of attraction between the oppositely charged particles.
Ionic compound properties • High melting and boiling point - The strong ionic bonds require a great deal of energy to overcome the forces of attraction between the ions. • Conduct electricity when molten (heated until it melts), ions are free to move and can carry charge around a circuit.
Conducting electricity �When an ionic compound is dissolved in water e. g. sodium chloride the ions are free to move. The charged sodium and chloride ions carry the charge through the salty water. Solutions of ionic compounds conduct electricity. Electrodes placed in salty water Electrodes placed in water
Plenary – True or false 1. Metal ions always have a negative charge. 2. When non-metal atoms form ions they gain electrons. 3. Ionic compounds have a high boiling point and a low melting point. 4. All ionic compounds are crystalline solids at room temperature. 5. When solid ionic compounds can conduct electricity.
Plenary – True or false 1. Metal ions always have a negative charge. F 2. When non-metal atoms form ions they gain electrons. T 3. Ionic compounds have a high boiling point and a low melting point. F 4. All ionic compounds are crystalline solids at room temperature. T 5. When solid ionic compounds can conduct electricity. F