NationStates Jolt Archive

I need to confirm the answers to the following questions:

Which formula is not correct?
(NH4)3PO4
Ba2CO3
Al2S3
MgS

Which of the following ionic compounds would have a name that contains the Roman numeral (III)?
AlCl3
FeBr3
Cu3N
more than one
none


Thanks ahead of time!

3. What is the correct name for SF6?
sulfur pentafloride?
4. Which formula is not correct?
(NH4)3PO4
Ba2CO3
Al2S3
MgS
bah...I need a periodic table...but just look at the charge on the ions and polyatomic ions. The net charge should be zero. When you find the one without a net charge of zero, that's the incorrect formula.
5. The formula and charge of the phosphate ion is PO43 -. What would be the formula and charge for the phosphite ion?
PO4 4-
PO4 3-
PO3 3-
PO3 2-
P03 3-
6. Which of the following ionic compounds would have a name that contains the Roman numeral (III)?
AlCl3
FeBr3
Cu3N
more than one
none

I think only FeBr3

I need to confirm the answers to the following questions:

Which formula is not correct?
(NH4)3PO4
Ba2CO3
Al2S3
MgS

Which of the following ionic compounds would have a name that contains the Roman numeral (III)?
AlCl3
FeBr3
Cu3N
more than one
none


Thanks ahead of time!

1. MgS, as Mg has a charge of 1+ and S is 2-.
2. Iron and Copper both use the Roman numeral nomenclature, but I'm not sure if one would use them in those compounds. Haven't worked with those in a while. Yay organic chemistry.

Thanks, Opal and Amyst!

I can't do nomenclature to save my life... and we had a lab on it last week and I'm trying to do the work for it before my lab tomorrow.

Thanks, again!!!

sulfur pentafloride?

SF6 would be sulfur hexafluoride.

1. MgS, as Mg has a charge of 1+ and S is 2-.
2. Iron and Copper both use the Roman numeral nomenclature, but I'm not sure if one would use them in those compounds. Haven't worked with those in a while. Yay organic chemistry.
Mg is +2...it's in 2A

Copper uses roman numeral, but in that problem, it was Cu3N...so unless Nitrogen has a -9 charge, Cu doesn't use the III in that situation.


And Amyst is correct, it's hexaflouride, not pentaflouride. Sorry.

Mg is +2...it's in 2A

Copper uses roman numeral, but in that problem, it was Cu3N...so unless Nitrogen has a -9 charge, Cu doesn't use the III in that situation.


And Amyst is correct, it's hexaflouride, not pentaflouride. Sorry.

My God, what was I thinking with Mg? *L* Thanks for catching that. I guess I'm rustier than I thought on inorganic stuff.

Cu could use I though, as in copper (I) nitride. But as has been demonstrated, my skill with inorganics kind of sucks now.

Edit: Ba2CO3 is incorrect. Ba is 2+, and CO3 is 2-, so it should only have one Ba.

My God, what was I thinking with Mg? *L* Thanks for catching that. I guess I'm rustier than I thought on inorganic stuff.

Cu could use I though, as in copper (I) nitride. But as has been demonstrated, my skill with inorganics kind of sucks now.
Well, I don't think too badly of you because if you would've asked me a few months ago, I would've been really rusty. I bet Tuesday Heights is in UCI or CCI, and guess what? I'm in UCI too (but wishing I was in UCII)

but as far as the second question goes, I don't hardly know any of the polyatomics so I'm sure it's one of them...your chem book should have a chart with all the polyatomics as well as their charge. I'd get mine out and tell you the answer...but it's your homework and I'm lazy.

Well, I don't think too badly of you because if you would've asked me a few months ago, I would've been really rusty. I bet Tuesday Heights is in UCI or CCI, and guess what? I'm in UCI too (but wishing I was in UCII)

Heh, you're going to have to spell those out for me. I'm unfamiliar with "UCI" and such.

Heh, you're going to have to spell those out for me. I'm unfamiliar with "UCI" and such.
College chem I, University Chem I, University Chem II...
They're classes.

I'm taking a Gen. Organic and Biochemistry class at the 100 level.

College chem I, University Chem I, University Chem II...
They're classes.

Figured they were; just never seen those particular names for classes. My high school just had "chemistry" and my college doesn't use UC, CC, or whatever.



Also, in case it was missed, I edited a previous post to show Ba2CO3 as incorrect.

More fun questions:

How about these ones?

1. Bromine has how many valence elections?
2. Oxygen has how many valence electrons?
3. Which one is more electronegative?
a. carbon or oxygen
b. carbon or chlorine
c. oxyten or phosphorous
d. flourine or bromine
4. what is the electron pair geometry of water?
- linear, trigonal planar, or tetrahedral
5. what is the molecular geometry of water?
- linear, trigonal planar, tetrahedral, triogonal pyramidal, or bent
6. what is the election pair geometry of methane?
- linear, trigonal planar, or tertrahedral
7. what is the molecular geometry of methane?
- linear, trigonal planar, tetrahedral, trigonal pyramidal, or bent

I'm taking a Gen. Organic and Biochemistry class at the 100 level.
Oh...that means next you'll be stuck doing all the carbons...
I hate memorizing things...there is a lot more memorization involved if you head towards organic..

The following answers are based off my sketchy memory of high school chemistry; they may or may not be accurate.
1. Bromine has how many valence elections?
7
2. Oxygen has how many valence electrons?
6
3. Which one is more electronegative?
a. carbon or oxygen
b. carbon or chlorine
c. oxyten or phosphorous
d. flourine or bromine
Oxygen, Chlorine, Oxygen, Flourine
4. what is the electron pair geometry of water?
- linear, trigonal planar, or tetrahedral
I would guess trigonal
5. what is the molecular geometry of water?
- linear, trigonal planar, tetrahedral, triogonal pyramidal, or bent
Trigonal pyramidal?
6. what is the election pair geometry of methane?
- linear, trigonal planar, or tertrahedral
...I don't know what election pair geometry is...but I know what methane is and I'd guess linear.
7. what is the molecular geometry of methane?
- linear, trigonal planar, tetrahedral, trigonal pyramidal, or bent
linear...?

More fun questions:

How about these ones?

1. Bromine has how many valence elections?
2. Oxygen has how many valence electrons?
3. Which one is more electronegative?
a. carbon or oxygen
b. carbon or chlorine
c. oxyten or phosphorous
d. flourine or bromine
4. what is the electron pair geometry of water?
- linear, trigonal planar, or tetrahedral
5. what is the molecular geometry of water?
- linear, trigonal planar, tetrahedral, triogonal pyramidal, or bent
6. what is the election pair geometry of methane?
- linear, trigonal planar, or tertrahedral
7. what is the molecular geometry of methane?
- linear, trigonal planar, tetrahedral, trigonal pyramidal, or bent

These ones are all easily answered by looking at periodic table position, except for the geometry ones, which is more memorization plus a bit of sense about how these things like to fit together.

All right, I think I have them all right... arg, I hate chemistry. It's a general education credit for me, as I'm a journalism major... arg.

All right, I think I have them all right... arg, I hate chemistry. It's a general education credit for me, as I'm a journalism major... arg.

No wonder the questions are this simplistic. *L* I was sitting here thinking that last year's general chem class was far harder than this seems to be.

More fun questions:

How about these ones?

1. Bromine has how many valence elections?
7
2. Oxygen has how many valence electrons?
6
3. Which one is more electronegative?
a. carbon or oxygen

O
b. carbon or chlorine
Cl
c. oxyten or phosphorous
O
d. flourine or bromine
F
4. what is the electron pair geometry of water?
- tetrahedral
5. what is the molecular geometry of water?
- bent
6. what is the election pair geometry of methane?
- tertrahedral
7. what is the molecular geometry of methane?
- , tetrahedral,


I rule! hehe. sorry i missed the first chem questions

No wonder the questions are this simplistic. *L* I was sitting here thinking that last year's general chem class was far harder than this seems to be.

Yeah, my fiancee is a chemistry major and she makes fun of me all the time because she can do this stuff in her head and I spend hours at a time trying to get the right answers.

Thanks, everyone, for your help!

I rule! hehe. sorry i missed the first chem questions
Hmm, it's good to know I knew the ones I thought I knew perfectly and was completely off on the ones I was guessing on.

hehe... why don't you ask her then? although since I'm sitting on my break between chem classes, answering chem questions is really amusing to me.

I need to confirm the answers to the following questions:

Which formula is not correct?
(NH4)3PO4
Ba2CO3
Al2S3
MgS

Which of the following ionic compounds would have a name that contains the Roman numeral (III)?
AlCl3
FeBr3
Cu3N
more than one
none


Thanks ahead of time!
"NH4" is a +1 ion. "PO4" is (from memory) a -3 ion. So that's correct. If this info is relevant to your question: This is NOT a covalently-bonded compound.
"Ba" is a +2 ion. "CO3" has a -2 charge. So Ba2CO3 is incorrect. Amyst: I stand corrected; Thank you.
I don't remember the oxidation numbers of Aluminum or Sulfur. For "Al2S3" to be correct, Al must be +3 and S must be -2; check a periodic table.
I don't remember the oxidation numbers of Magnesium or Sulfur. For "MgS" to be correct, Magnesium and Sulfur must have equal-and-opposite oxidation numbers. Check a periodic table.

AlCl3 - Aluminum is not a transition metal. It doesn't get assigned a Roman numeral. Opal Isle: I stand corrected; Thank you.
FeBr3 - It looks like Iron (Fe) has an oxidation number of +3, here. III
Cu3N - It looks like Copper has an oxidation number of +1, here. I

More fun questions:

How about these ones?

1. Bromine has how many valence elections?
2. Oxygen has how many valence electrons?
3. Which one is more electronegative?
a. carbon or oxygen
b. carbon or chlorine
c. oxyten or phosphorous
d. flourine or bromine
4. what is the electron pair geometry of water?
- linear, trigonal planar, or tetrahedral
5. what is the molecular geometry of water?
- linear, trigonal planar, tetrahedral, triogonal pyramidal, or bent
6. what is the election pair geometry of methane?
- linear, trigonal planar, or tertrahedral
7. what is the molecular geometry of methane?
- linear, trigonal planar, tetrahedral, trigonal pyramidal, or bent
1. Bromine is a halogen; I think the answer is "7".
2. Oxygen has 6 valence electrons.
3a. Oxygen - It's the same period, but a higher group.
3b. I'm pretty sure it's chlorine, but check the electronegativity numbers on a periodic table.
3c. Oxygen - Both a higher group and a lower period (Oxygen is period 2, phosphorus is period 3).
REMEMBER: Electronegativity increases as you go up and right on the Periodic Table.
4. Tetrahedral. Oxygen, the central atom, has 2 single bonds and 2 lone pairs. (2+2=4)
5. Bent. There are only three atoms; not enough to be tetrahedral.
6. Tetrahedral. Carbon, the central atom, has 4 single bonds.
7. Also Tetrahedral.


Yeah, my fiancee is a chemistry major and she makes fun of me all the time because she can do this stuff in her head and I spend hours at a time trying to get the right answers.

Thanks, everyone, for your help!
I'm pretty sure that "Tuesday Heights" is female, so I'm guessing that you're her fiancee logging in on her account. Am I correct?


--The Democratic States of Cogitation
"Think about it for a moment."
Founder and Delegate of The Realm of Ambrosia

No Cog... they're both female :p

...


And I felt all smart after learning how the shells and suborbitals and pairings work and the definitions of ions and isotopes and why helium doesn't combine....

"NH4" is a +1 ion. "PO4" is (from memory) a -3 ion. So that's correct. If this info is relevant to your question: This is NOT a covalently-bonded compound.
"Ba" is a +2 ion. "CO3" is a -2 ion. So Ba2CO3 is incorrect. Amyst: I stand corrected; Thank you.
I don't remember the oxidation numbers of Aluminum or Sulfur. For "Al2S3" to be correct, Al must be +3 and S must be -2; check a periodic table.
I don't remember the oxidation numbers of Magnesium or Sulfur. For "MgS" to be correct, Magnesium and Sulfur must have equal-and-opposite oxidation numbers. Check a periodic table.

AlCl3 - It looks like Aluminum has an oxidation number of +3, here. III
FeBr3 - It looks like Iron (Fe) has an oxidation number of +3, here. III
Cu3N - It looks like Copper has an oxidation number of +1, here. I
Aluminum is not a transition metal and doesn't get assigned Roman Numerals. It's always +3. Iron and Copper get assigned Roman Numerals because they don't always have to be the same ion. The Roman Numeral signifies what ion you're talking about.

Also, although oxidation numbers are the same as the charge of the ion, oxidation number really is the incorrect term to use here as Oxygen has an oxidation number of -2 (most of the time), but it typically isn't found in ionic compounds. Only covalent bonds...

Here's a fun idea, draw the full structural formula of this:

1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-butyldecan-2,10-diol.

The side chains should probably be in a different order, alphabetical or something, but whatever. :)

Bonus points for using coloured pens. ;)

Peace!

Here's a fun idea, draw the full structural formula of this:

1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-butyldecan-2,10-diol.

The side chains should probably be in a different order, alphabetical or something, but whatever. :)

Bonus points for using coloured pens. ;)

Peace!

I'm suddenly stricken with horrid flashbacks to the midterm I took yesterday, which had just this kind of question.

For this, I hate you.

Edit: Actually, 2,10-diol? In a decane-based structure? Shouldn't that be 1,9-diol with the rest of the substituents summarily changed in locant?

Edit2: Not to mention, counting the backbone from the butyl group would give you a dodecane molecule, as that chain of carbons would be the longest.

Edit3: Edit2 there might be nonsense, if the ol groups actually trump the longer chain. I don't know how those work in IUPAC naming conventions as I just went over this stuff a few days ago.

No Cog... they're both female :p
A homosexual relationship?

Three possibilities:

"Tuesday Heights" and her fiancee live someplace where homosexual marraige is legal.
"Tuesday Heights" and her "fiancee" are using the term "fiancee" very loosely.
"Erastide" is pulling my leg.


If either of the first two, then I shrug, smile, and say "Whatever floats your boat. Congratulations on finding happiness." If the third, then I will make plans to do something hilarious at Erastides expense.

Here's a fun idea, draw the full structural formula of this:

1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-butyldecan-2,10-diol.

The side chains should probably be in a different order, alphabetical or something, but whatever. :)

Bonus points for using coloured pens. ;)

Peace!
I'm not sure, but I think it's this:
[Ignore periods; they're there to keep the chain straight.]

H
|
Cl- C -Cl
|
..HO- C -CH3
|
H- C -H
|
...H- C -CH3
|
.....H- C -C3H7
|
...H- C -CH3
|
.....H- C -C2H5
|
.....H- C -C4H9
|
H- C -H
|
H- C -H
|
OH
--The Democratic States of Cogitation

*snipped structure here*

That's what I got, but then I wondered about the structure given, and whether it's following the correct naming conventions.

That's what I got, but then I wondered about the structure given, and whether it's following the correct naming conventions.
Actually, I don't think that it is.

Look at the butyl group on carbon 8: You're supposed to lay out the longest carbon chain, so the main line should have followed what's being drawn as a butyl side group.

So, this is really:
1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-[something]dodecan-2-ol

Unfortunately, I don't know how to name a -C2H4OH side group, and it should go where that "[something]" is.

This doesn't show up in the NIST Chemistry Webbook (http://webbook.nist.gov). Why am I not surprised?

--The Democratic States of Cogitation

Actually, I don't think that it is.

Look at the propyl group on carbon 8: You're supposed to lay out the longest carbon chain, so the main line should have followed what's being drawn as a propyl side group.

So, this is really:
1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-[something]dodecan-2-ol

Unfortunately, I don't know how to name a -C2H4OH side group, and should go where that "[something]" is.

--The Democratic States of Cogitation

I assume you meant the butyl group on carbon 8. That's what I was getting at.

Also, even ignoring that, the end that would give the lowest number to the ol group would be carbon 1, so the 2,10-diol should've been 1,9-diol with the rest of the locants changed as necessary.
Edit: Unless the halide (the dichloro in this case) trumps the ol in numbering priority. I don't know.

I assume you meant the butyl group on carbon 8. That's what I was getting at.
I caught the error and edited it while you were still typing. ;)

Also, even ignoring that, the end that would give the lowest number to the ol group would be carbon 1, so the 2,10-diol should've been 1,9-diol with the rest of the locants changed as necessary.
Edit: Unless the halide (the dichloro in this case) trumps the ol in numbering priority. I don't know.
True, true. Howver, if you relay the chain as a dodecanol, rather than a decanol, then that -OH group winds up on a side chain. Do -OH groups on side chains count in this?

Actually, I'm not doing all that bad for someone who hasn't taken (or used) Organic Chemistry in 5 years. :D

--The Democratic States of Cogitation

I caught the error and edited it while you were still typing. ;)

Damn your editing prowess!


True, true. Howver, if you relay the chain as a dodecanol, rather than a decanol, then that -OH group winds up on a side chain. Do -OH groups on side chains count in this?

--The Democratic States of Cogitation

No idea. I had actually noticed the ol problem before the dodecane vs decane problem, and I meant to indicate that even if the chain was properly named as a decane, the ol groups would change the numbering. I don't know about side chains with -OH groups.

Edit: Five years? *L* Good to know this will still be crowding my brain that far down the road, heh.

I've got to head out to band practice now (gotta help the team beat uc berkeley this weekend!) so I'll make any further comments on this dodecane problem later in the evening. Thanks for the discussion, heh.

True, true. Howver, if you relay the chain as a dodecanol, rather than a decanol, then that -OH group winds up on a side chain. Do -OH groups on side chains count in this?

Actually, I'm not doing all that bad for someone who hasn't taken (or used) Organic Chemistry in 5 years. :D

--The Democratic States of Cogitation

ooo.. think I got it off of IUPACs website.

So you do a little [] and you're good.

So...
1-Dichloro-2,4,6-trimethyl-5-propyl-7-ethyl-8-[1-hydroxyethyl]dodecan-2-ol

And I think it's now about 5 years for me too since OChem. wow... I didn't ever want to have to remember this stuff. :p

A homosexual relationship?

Three possibilities:

"Tuesday Heights" and her fiancee live someplace where homosexual marraige is legal.
"Tuesday Heights" and her "fiancee" are using the term "fiancee" very loosely.
"Erastide" is pulling my leg.


If either of the first two, then I shrug, smile, and say "Whatever floats your boat. Congratulations on finding happiness." If the third, then I will make plans to do something hilarious at Erastides expense.

lol. I'm glad this thread has turned into a discussion on my personal chemistry with other people. It made me smile.

For the record, everyone:

I am a lesbian.
I am engaged to another female; and living in Pennsylvania, where homosexual marriage/civil unions are not legal.
We are engaged, hence the term, "fiancee" being used.


I'm going to link to this post in my signature for all to see. Hehe. :)

I'm not sure, but I think it's this:
[Ignore periods; they're there to keep the chain straight.]

H
|
Cl- C -Cl
|
..HO- C -CH3
|
H- C -H
|
...H- C -CH3
|
.....H- C -C3H7
|
...H- C -CH3
|
.....H- C -C2H5
|
.....H- C -C4H9
|
H- C -H
|
H- C -H
|
OH
--The Democratic States of Cogitation

Great! :) That's probably right....

Can anyone come up with a name for an organic molecule that looks like a Christmas tree? Maybe some Halogens for baubles coming off the branches and a phenyl group at the top for a star type thing. :D

lol. I'm glad this thread has turned into a discussion on my personal chemistry with other people. It made me smile.

For the record, everyone:

I am a lesbian.
I am engaged to another female; and living in Pennsylvania, where homosexual marriage/civil unions are not legal.
We are engaged, hence the term, "fiancee" being used.


I'm going to link to this post in my signature for all to see. Hehe. :)

Thanks TH. I was scared Cog was going to do something funny to my nation. (as fun as that would be to see) :p

Oh, and here's to you being *actually* able to marry sometime in the future.

And to chemistry! Ask for help anytime! It's better than answering my own students' questions. :rolleyes:

Thanks, Erastide!!!

I've never been that great at math and science, so, when I can, I try to get a heads up on the right answers so I can correct my mistakes and go back over them so I can get a decent grade.

Thanks, everyone, for your help!

Do you mind me asking what you study?