The particulate nature of matter Flashcards
Define ionic bonds.
Ionic bonds are strong electrostatic forces of attraction between oppositely charged ions.
Describe the structure of ionic compounds.
Ionic compounds consist of positive ions of metals and negative ions of non-metals. Since the structure consists of a large number of ions, ionic compounds have a giant ionic crystal lattice structure.
State the states of matter for which ionic compounds conduct electricity.
Molten and aqueous state
How are covalent bonds formed?
Covalent bonding is the result when atoms are joined together by sharing of electrons, forming molecules.
Give examples of giant molecular structures.
Diamond, graphite, and silicon dioxide
Define metallic bonds.
The strong electrostatic force of attraction between the positively charged ions and the negatively charged delocalised electrons. It is this force of attraction, which holds the cations and electrons together.
Explain why metals are good conductors of electricity.
Metals are good conductor of electricity because there exist a ‘sea of delocalised mobile negatively charged electrons’ available within the giant metal lattice structure to move and carry the negative electric charge to conduct electricity.
Explain why metals are good conductors of heat.
Metals are good conductors of heat because heat is transferred easily by the surrounding ‘sea of delocalised mobile negatively charged valence electrons’ in the giant metal lattice structure. The electrons move freely to transfer heat.
Explain why metals have high densities.
Atoms in the giant metal lattice structure are packed tightly in an orderly and rigid layer arrangement. Hence, the high density.
Explain why metals have high melting and boiling points.
Since metallic bonding is the strong electrostatic force of attraction between the positively charged metal ions and the surrounding ‘sea of delocalised mobile negatively charge valence electrons’, a large amount of heat energy is required to overcome these strong electrostatic forces of attraction. Hence, metals have high melting and boiling points.
Explain why metals are ductile and malleable.
When a force is applied to a metal, the layers of atoms can slide through the surrounding ‘sea of delocalised mobile negatively charged valence electrons’ without disrupting the metal lattice as there is metallic bonding between the metal ions and sea of electrons. Before a force is applied, the metal atoms forms an orderly and rigid arrangement. When a force is applied, one layer of metal ions slides over the other through the surrounding ‘sea of electrons’. Hence, metallic bonds are strong but flexible, so metals are malleable and ductile.
Describe the arrangement of particles in solids.
- Particles are very closely packed together
- Fixed in an orderly arrangement
- Particles vibrate about their fixed positions
Describe the arrangement of particles in liquids.
- Particles are closely packed together
- Disorderly with no fixed positions
- Particles can slide past one another
Describe the arrangement of particles in gases.
- Particles are far apart
- Particles are in random arrangement
- Particles can move about freely in any direction at high speeds, occupying any available space.
Define kinetic particle theory.
The kinetic particle theory states that all matter is made up of tiny particles and that these particles are in continuous random motion.
