7 Written questions
6 Multiple choice questions
- Poor: ionic lattices are rigid and once broken tend to cleave along an entire plane.
- Soluble: the charged ions interact with the dipoles on the water molecules.
- Alloy formation sometimes alters the chemistry such as the formation of a chemically inert oxide layer in stainless steel.
- Insoluble: ionic compounds tend not to dissolve in nonpolar solvents because the attractions between ions are much more favorable than the attractions among the separated ions and nonpolar solvent molecules.
- Malleable and ductile: deforming the solid does not change the environment immediately surrounding each metal core
- Shiny, reflective, lustrous: because electrons move freely throughout the metal. Metals are shiny because of the very strong absorption of light by the delocalised bonding electrons.
6 True/False questions
Conductivity of an ionic solid → Good: electrons are delocalized and relatively free to move
Hardness of an ionic solid → Hard: ionic lattice is strong and rigid
Alloys → Metallic mixtures
Substitutional Alloy (definition) → formed between atoms of comparable radius, where one atom substitutes for the other in the lattice
Optical properties of metal (explained) → When light falls on a metal it is almost totally absorbed since the bonding electrons can jump up to a broad band of energy levels allowing energy changes corresponding to the full range of frequencies in the visible region of the spectrum.
These currents immediately re-emit the light out of the metal thus providing a strong reflection if the metal surface is smooth.
Interstitial Alloy (properties) → interstitial atoms do not appreciably expand the lattice and so density is often substantially increased; interstitial atoms make the lattice more rigid reducing ductility and malleability