Wednesday, February 25, 2009

i've learnt quite a number of things in chem class today. i have learnt how to write balanced equations, find out the problem, purpose of the question. i also learnt how to identify if the reaction is a chemical/ physical reaction.

Monday, February 23, 2009

i've learnt many things.
some examples of binary covalent componds are water and ammonia. i've also learnt about prefixes. they are :
Prefixes
1 - mon(o)
2 - di
3 - tri
4 - tetr(a)
5 - pent(a)
6 - hex(a)
7 - hept(a)
8 - oct(a)
9 - non(a)
10 - dec(a)
Roots of the Nonmetals
H - hyd
C - carb
N - nitr
P - phosph
As - arsen
O - ox
S - sulf
Se - selen
F - fluor
Cl - chlor
Br - brom
I - iod

i also learnt that Metallic atoms hold some of their electrons relatively loosely, and as a result, they tend to lose electrons and form cations. i also know that when a metallic element and a nonmetallic element combine, the nonmetallic atoms often pull one or more electrons far enough away from the metallic atoms to form ions. The positive cations and the negative anions then attract each other to form ionic bonds.