NCEA Level 2 Chemistry: Exam revision Structure and bonding
Posted by: john west in UncategorizedTo get the best results in this achievement standard you need be clear about how you organise your answers.
All the basic material you need to know about is covered in three short videos, a complete course reduced to 15 mins!
The first video deals with covalent bonding Lewis structures and Lewis diagrams. There is a short quiz at the end of it.
The second video deals with molecular shape and polarity
The third video deals with metallic and ionic bonding. It also examines properties such as malleabilityor ductility and conductivity when molten or in aqueous solution. The solubility of ionic compounds in aqueous solution is also discussed.
good luck
Tabun and sarin were among the agents used by the Iraqi government when it killed 5,000 Iraqi Kurds in Halabja in 1988. Liquid sarin in perforated bags killed 12 people in the 1995 attack on the Tokyo underground.
Civil engineers are skilled in the use of science and mathematics to build structures that don’t fall over. The Auckland Harbour Bridge needed extra capacity hence the addition of nippon clipons in 1965. The two-lane box girder sections added on each side of the bridge doubled the traffic lanes to eight. Structures must be maintained and cracks discovered in 1987 and cracks/material fatigue found in 2006 could not be ignored. Generally engineers get it right and we trust their safety margins. Currently vehicles are restricted to weights of 13 tonnes or less after further concerns that a traffic jam stopping flow on the bridge could cause the clip-ons to unclip.

Entries (RSS)