Chemistry test on Naming tomorrow!

hey guys,

I know we all are freaking out for the test of Ms Rosu tomorrow, so anyone having any doubt, issue, or suiscide desire are encouraged to post here (I'll be connected so I will answer you anyway)

The goal is to be the best junior class ever
Don't be discouraged by any previous quizz grade, test grade worths more!!!

basic explanation on naming/recognizing acids please =D

There are two types of acids:
Binary acids --
ex. HCl (aq.) state=liquid
hydrochloric acid
HBr (aq.)
hydrobromic acid
HCl (g.) state=gas
hydrogen monochloride

Depending on the state of the formula you will write the naming in two different ways, either the simple one with greek prefix (for GAS) or the "ic" acid (for the LIQUID). They're always "hydro" because of the hydrogen atom to the left of the formula.

Oxyacids --
these are the ones containing the polyatomic ions we already know
ex. H2SO4
sulfuric acid
H3PO4
phosphoric acid
HClO3
chloric acid
H2CO3
carbonic acid
HNO3
nitric acid
CH3COOH
acetic acid

It must also be understood that they can be, for example, sulforIC or sulfurOUS depending on the number of oxygens, if they have 1 less or 2 less oxygen molecules the naming will be sulfurOUS and if they have the same number or 1 more oxygen they will be sulfurIC. Was that clear?

Look at the naming table for the polyatomic ions we know (with hydrogen):
PERSULFATE - persulfuric acid
SULFATE - sulfuric acid
SULFITE - sulfurous acid
HYPOSULFITE - hyposulfurous

clear. but death is still eminent.
by the way, do all binary acids hv only 1 hydrogen?

Thanks Bibi for the complete explanation on acids

Ana, binary acids are formed by putting a hydrogen before the element.
But on the contrary of Oxyacids, the crossover does not apply:

H and Cl => HCl

H and (SO4)2+ => H2SO4 (cross over)

Binary acids are an exception to the cross over of the charges. But that's important to determine if they are liquid (aq) or (g), for the naming is different.

Hope it helped

aaaaaaaaah! i'm freaking out here, guys! hahahaha

make it two people freaking out!

i dont even know the binary whatevers. It cant be worse.

ixi da 1 aula ai.......alguem..........

guys, i have a question that goes back to the ionic compounds with transition metals - i always get confused

If I have, let's say, MnCLsub4, what's the process to get manganese (IV) chloride? do we just do the cross-over thing backwards?

usually yes mai. i cant really think of an exception.
think about it... you hv electrons added to each of the chlorines. meaning u needed four. But u used only 1 Mn atom (since the formula does not hv a subscript for it) therefore you question: which one would hv the number of electrons needed? tadaaam

Relax. Binaries bi => two

That's two elements associated (forming thus a compound)

two kinds of binaries => Covalents (2 non-metals)
=> Ionic (1 non-metal and 1 metal)

Covalent are easy: H2O : di(2)hydrogen mono(1)oxyde

Ionic are even more: first write the name of the metal, then write the name of the non-metal, with ending -ide.

EX: Si O2 => Silicon Oxyde

For the cross over rule, are you familiar with it ?
If not, just count the valence electrons (how many it needs to become a noble gas); these valences are charges

for example Ca has two charges (2+) and Sulfur two (2-)
then those charges are placed on the opposite element (in the case of calcium and sulfur they just cancel out 2-2=0)

another example; Na+ and N3-

the + goes to N and the 3- goes to Na => Na3 N

if there are other doubts, ot if it is confused , ask me!

Ana, since Silicon has 4- charges and Mn 4+ I think they simply cancel out

the trick with transition metals is to look up the other element's charge -- and try to cancel it.

For instance, Chromium (Cr) has 2+ or 3+

Associated with Nitrogen (N), which has 3-, the best for Chromium is to be Cr(III) to cancel out the charges of Nitrogen

so => CrN instead of Cr3N2

ok guys i have a major problem i dont understand this .....
why is lead (II) sulfite => Pb( SO3)
instead of Pb (SO4)2

basically im asking when it ask fo 1 or 2 less do i take it out from the top or bottom number????

hey jess! well
if lead is 2 and the polyatomic ion of sulfur has valence o 2, their valences cancel!
it is 3 instead of 4 because it is ITE, sulfITE not sulfFATE!

did you understand?
kiss

thanks bia
kisses

Guys! on the worksheet with the naming problems... there are two I think Ms. Rosu didn't teach us!
its Chromic bisulfate and Potassium permanganate!!

Exactly Milla ... the "bi" thing and the "per" before a transition metal are some of the naming surprises coming on in the near future in Chemistry class

let's focus on what we already have to do

mlla, manganate is in our notes! MnO base 4 valence -1
however i dont think she thought us bisulfate
kissy

lead (II) = Pb2
sulfite = SOsub3 2minus... sulfate is the one that = SOsub4 2 minus

so Pb2 and (SO3)2
the two cancel out and you have Pb(SO3)

hey Bia,
Ok for the bi, but permanganate I don't have in my notes

wow... I posted a reply and there were already like 4 posts answering it! Hehehe
This is great!
Chemistry test tomorrow? Not so great...

THIS IS AWESOME!!! (the participation though, not the test )
I am very glad of the cooperation btw everyone in that topic!!! That's exactly what this forum intends to do

AHHH!!! thanks bia! found permanganate in my notes too! xD