Need Help with Chemistry (1 Viewer)

[HiHaii]

Just a few things I'm not sure of and need to be corrected

Formula for

• Aluminium sulfate (does the '3's cancel out?)
• Lead IV sulfate
• Ammonium carbonate

Lewis structure for OBr2

Appropriate name for PBr5

how do i find the empirical formula of the minerals Boehmite, Gibbsite and Diaspore?
Given that the composition of:
Boehmite is 44.98% Al, 53.34% O, 1.68% H (Density: 3.1, Hardness: 3)
Gibbsite is 34.59% Al, 61.54% O, 3.88% H (Density: 2.4, Hardness: 2.5-3.5)
Diaspore is 44.98% Al, 53.34% O, 1.68% H (Density: 3.3-3.5, Hardness 6.5-7)

 

[ohexploitable]

Aluminium Sulfate: Al₂(SO₄)₃
Lead (IV) Sulfate: Pb(SO₄)₂
Ammonium Carbonate: (NH₄)₂CaCO₃

PBr₅: Phosphorus penta-bromide

 

[ohexploitable]

OBr₂

 

[HiHaii]

thanks!

few more questions regarding the previous, lets say for example...
if you have two same numbers, do they cancel out?
like AB2(XY3)3

and when do you add an 'a' at the end of the prefix? pent becomes penta-...

 

[ohexploitable]

The prefixes are confuddling, like it's tetrasulfide but tetroxide. I don't think it matters too much, you're not gonna get marked down.

But I'm pretty sure it's pentabromide.

 

[ohexploitable]

thanks!

few more questions regarding the previous, lets say for example...
if you have two same numbers, do they cancel out?
like AB2(XY3)3

and when do you add an 'a' at the end of the prefix? pent becomes penta-...

They don't cancel out, treat XY₃ as a separate thingy. Like you need three XY₃ things to balance AB₂.

 

[HiHaii]

-How do you write OBr2 as a compound? not a diagram

-will it stay as AB2(XY3)3 or you mean AB2XY?

 

[ohexploitable]

-How do you write OBr2 as a compound? not a diagram

-will it stay as AB2(XY3)3 or you mean AB2XY?

What do you mean "OBr₂ as a compound"?

It stays as AB₂(XY₃)₃.

 

[hscishard]

It's so hard reading forumals with no subscripts.

For the cancelling out part yes you do.
But if you choose to use the cross method:
E.g. Mg^2+ and Oxygen^2-

It is just MgO

Mg(2)O(2). This is kind of correct, but questions like this usually ask for the emperial form(simplest ratio).

Mg(2)O(2) = 2:2 = 1:1 = MgO
Therefore it is just MgO

 

[hscishard]

-How do you write OBr2 as a compound? not a diagram

-will it stay as AB2(XY3)3 or you mean AB2XY?

What do you mean by write as a compound?
If you mean using words to name it...
It's Oxygen dibromide, I think. You don't put mono for the oxygen (it is in front)

 

[hscishard]

Aluminium Sulfate: Al₂(SO₄)₃
Lead (IV) Sulfate: Pb(SO₄)₂
Ammonium Carbonate: (NH₄)₂CaCO₃

PBr₅: Phosphorus penta-bromide

You sure about that lead sulfate?

I got Pb(2)[SO(3)]3

I think Latex can be used for these things

Whoops IV is 4. Shit, stupid romans

 

[ohexploitable]

It's so hard reading forumals with no subscripts.

For the cancelling out part yes you do.
But if you choose to use the cross method:
E.g. Mg^2+ and Oxygen^2-

It is just MgO

Mg(2)O(2). This is kind of correct, but questions like this usually ask for the emperial form(simplest ratio).

Mg(2)O(2) = 2:2 = 1:1 = MgO
Therefore it is just MgO

OP meant if the subscript in the bracket was the same as the subscript outside the bracket should they cancel? You don't cancel.

Like aluminium nitrate, Al(NO₃)₃ doesn't become AlNO.

 

[ohexploitable]

You sure about that lead sulfate?

I got Pb(2)[SO(3)]3

I think Latex can be used for these things

Lead (IV) is Pb⁴⁺, sulfate is SO₄^2-, so you need 2 sulfates per lead.

 

[hscishard]

OP meant if the subscript in the bracket was the same as the subscript outside the bracket should they cancel? You don't cancel.

Like aluminium nitrate, Al(NO₃)₃ doesn't become AlNO.

We(poster and I) need to use latex. Lol
That was hell confusing.

 

[ohexploitable]

Just use _subscript and ^superscript tags.

 

[hscishard]

Lead (IV) is Pb⁴⁺, sulfate is SO₄^2-, so you need 2 sulfates per lead.

Ya, I saw IV as 3-.-

 

[ohexploitable]

lol there's no such thing as Pb(III), only Pb(II) and Pb(IV).

 

[ohexploitable]

I think Latex can be used for these things

 

[hscishard]

lol there's no such thing as Pb(III), only Pb(II) and Pb(IV).

How do you know that? Theres so many things to remember in chem.

 

[ohexploitable]

How do you know that? Theres so many things to remember in chem.

It just is, I'm not sure why, I think it has something to do with the electron shells.