This discussion is now closed.
Check out other Related discussions
- Help with AS level chemistry question
- Atomic Subshells
- A-Level Chemistry HELP !!!
- A level chemistry
- Dative or coordinate bonding URGENT
- how do you work out if soemthing has a vacant orbital for dative bonding
- Atomic Structure - Shapes of S and P orbitals AQA a level chem
- A level chemistry questions
- Group number correspondence on periodic table
- P orbitals A-level Chemistry
- Chemistry OCR A
- Chem question: How many orbitals are occupied in a silicon atom?
- should I choose A level chemistry
- Ask Us Anything!
- Chem a level
- Urgent a level chem help!!!
- A-level complex Dot and Cross diagrams
- Electron Configuration of Zinc (Zn)
- A level chemistry question
- Chemistry A level basics need help
AS Chemistry Orbitals and Sub shells Help!!
Can someone please explain sub shells and orbitals to me please?
My chemistry teacher is awful and just basically wrote a load of stuff on the board and told us to copy it, and I tried to understand but I'm so confused
My chemistry teacher is awful and just basically wrote a load of stuff on the board and told us to copy it, and I tried to understand but I'm so confused
Scroll to see replies
orbitals contain two electrons, one or more orbitals make up subshells, one or more subshells make up a shell
At GCSE you were told that electronic configurations go in the order 2, 8, 8 etc.
This isn't really the case (it's actually a simplification), each shell can be subdivided into further levels called subshells - the subshells are denoted s, p, d, and f (stand for sharp, principal, diffuse and fundamental)
For example if we take the second shell (which has 8 electrons) it has two subshells (two sets of electrons with differing energy, although similar) 2s and 2p the s subshell hols two electrons and the p subshell holds 6 electrons
An orbital is a further subdivision of a subshell - s has 1 orbital and p has 3 orbitals - each orbital can only hold two electrons (one with spin up and one with spin down)
At GCSE you were told that electronic configurations go in the order 2, 8, 8 etc.
This isn't really the case (it's actually a simplification), each shell can be subdivided into further levels called subshells - the subshells are denoted s, p, d, and f (stand for sharp, principal, diffuse and fundamental)
For example if we take the second shell (which has 8 electrons) it has two subshells (two sets of electrons with differing energy, although similar) 2s and 2p the s subshell hols two electrons and the p subshell holds 6 electrons
An orbital is a further subdivision of a subshell - s has 1 orbital and p has 3 orbitals - each orbital can only hold two electrons (one with spin up and one with spin down)
EierVonSatan
This isn't really the case (it's actually a simplification), each shell can be subdivided into further levels called subshells - the subshells are denoted s, p, d, and f (stand for sharp, principal, diffuse and fundamental)
Just out of curiosity really, but the s subshell is spherical, the p subshell is hourglass/figure-of-eight, what shape is a d and f subshell? And isn't there an extra type of subshell for lanthanides and actanides? Or was that just a very geeky dream?
So you know that in 'shells' there can be so many numbers of electrons
1st = 2 electrons
2nd = 8 electrons
3rd = 18 electrons
4th = 32 electrons
so for sodium, which contains 11 electrons, has an electron arrangement of 2,8,1.
Two electrons filling the first shell, eight electrons filling the second shell and one electron in the outer third shell.
However, that's just a simplified version of it, you can break this down into sub-shells.
You can't locate exactly where an electron is but you can see where about they are, this region is known as an orbital.
Orbitals then get divded into s, p, d and f.
The first energy level holds 2 electrons in an s type orbital called 1s. There are no p, d, or f orbitals available at this energy level.
The second energy level holds 8 electrons and is made up of one s type orbital, 2s and then 3 p type orbitals. These four together hold the 8 so it will look like 2s2 2p6 (as there are 3ps holding 2 in each).
The third energy level consists of one s type orbital, three p type orbitals and 5 d type orbitals. These nine orbitals can hold a maximum of 18 electrons altogether.
You need to remember when filling the orbitals that...
1. Electrons fill the lowest energy orbitals first and the other orbitals in order of ascending energy.
2. Where there are several orbitals of exactly the same energy e.g. three 2p orbitals, electrons will occupy different orbitals whenever possible.
And of course "When an orbital only contains 1 electron then this electron is said to be unpaired."
Also electron arrangement may be abbreviated.
Back to my original example of Sodium, the electronic structure is 1s2 2s2 2p6 3s1.
I hope that makes more sense
1st = 2 electrons
2nd = 8 electrons
3rd = 18 electrons
4th = 32 electrons
so for sodium, which contains 11 electrons, has an electron arrangement of 2,8,1.
Two electrons filling the first shell, eight electrons filling the second shell and one electron in the outer third shell.
However, that's just a simplified version of it, you can break this down into sub-shells.
You can't locate exactly where an electron is but you can see where about they are, this region is known as an orbital.
Orbitals then get divded into s, p, d and f.
The first energy level holds 2 electrons in an s type orbital called 1s. There are no p, d, or f orbitals available at this energy level.
The second energy level holds 8 electrons and is made up of one s type orbital, 2s and then 3 p type orbitals. These four together hold the 8 so it will look like 2s2 2p6 (as there are 3ps holding 2 in each).
The third energy level consists of one s type orbital, three p type orbitals and 5 d type orbitals. These nine orbitals can hold a maximum of 18 electrons altogether.
You need to remember when filling the orbitals that...
1. Electrons fill the lowest energy orbitals first and the other orbitals in order of ascending energy.
2. Where there are several orbitals of exactly the same energy e.g. three 2p orbitals, electrons will occupy different orbitals whenever possible.
And of course "When an orbital only contains 1 electron then this electron is said to be unpaired."
Also electron arrangement may be abbreviated.
Back to my original example of Sodium, the electronic structure is 1s2 2s2 2p6 3s1.
I hope that makes more sense
deadgenius
Just out of curiosity really, but the s subshell is spherical, the p subshell is hourglass/figure-of-eight, what shape is a d and f subshell? And isn't there an extra type of subshell for lanthanides and actanides? Or was that just a very geeky dream?
The d orbital is like the p orbital with the hourglass, but its like there are 2 hourglasses on the 3-D axis.
Similarly the f orbital can have 4 hourglass shapes on the 3-D axis.
You can get a g orbital too, well I think thats what I heard
deadgenius
Just out of curiosity really, but the s subshell is spherical, the p subshell is hourglass/figure-of-eight, what shape is a d and f subshell? And isn't there an extra type of subshell for lanthanides and actanides? Or was that just a very geeky dream?
s are round, p are hourglass, 4/5ths of the d orbitals are 'double' hourglasses (4 lobes) the fifth lobe is like a p orbital with a ring around it. The f subshells are more complicated looking things (8 lobes for most). the lanthanides and actanides use the f orbitals, but there is a g subshell too (18 electrons) and i have no idea what they look like
EierVonSatan
orbitals contain two electrons, one or more orbitals make up subshells, one or more subshells make up a shell
At GCSE you were told that electronic configurations go in the order 2, 8, 8 etc.
This isn't really the case (it's actually a simplification), each shell can be subdivided into further levels called subshells - the subshells are denoted s, p, d, and f (stand for sharp, principal, diffuse and fundamental)
For example if we take the second shell (which has 8 electrons) it has two subshells (two sets of electrons with differing energy, although similar) 2s and 2p the s subshell hols two electrons and the p subshell holds 6 electrons
An orbital is a further subdivision of a subshell - s has 1 orbital and p has 3 orbitals - each orbital can only hold two electrons (one with spin up and one with spin down)
At GCSE you were told that electronic configurations go in the order 2, 8, 8 etc.
This isn't really the case (it's actually a simplification), each shell can be subdivided into further levels called subshells - the subshells are denoted s, p, d, and f (stand for sharp, principal, diffuse and fundamental)
For example if we take the second shell (which has 8 electrons) it has two subshells (two sets of electrons with differing energy, although similar) 2s and 2p the s subshell hols two electrons and the p subshell holds 6 electrons
An orbital is a further subdivision of a subshell - s has 1 orbital and p has 3 orbitals - each orbital can only hold two electrons (one with spin up and one with spin down)
Right thankyou I think I understand
But why is it 2s 2p? Does that mean that there are 2 s subshells and 2 p subshells?
bob9001
Right thankyou I think I understand
But why is it 2s 2p? Does that mean that there are 2 s subshells and 2 p subshells?
But why is it 2s 2p? Does that mean that there are 2 s subshells and 2 p subshells?
2 is just the shell number
so the second shell has one s subshell called 2s and one p subshell called 2p
EierVonSatan
2 is just the shell number
Ohh I seee...thankyou
and thankyou everyone I think I understand!
Would you be able to take me through the electron configuration for magnesium for example?
Mg at GCSE is 2,8,2
which is more precisely {1s2,}, {2s22p6},{3s2}
which is more precisely {1s2,}, {2s22p6},{3s2}
http://www.4college.co.uk/as/index.php >> Minerals to Elements >> Atomic Orbitals
http://www.chemguide.co.uk/atoms/properties/atomorbs.html#top
The advice from lucyhol1012 is brilliant, but just to add to the confusion(!) there is exceptions to the rule of filling up shells that you will probably need to know for the exam:
Copper and chromium do not follow the general rule for filling up shells.
Copper has the configuration: 1s2 2s2 2p6 3s2 3p6 4s1 3d10, not 1s2 2s2 2p6 3s2 3p6 4s2 3d9
Chromium has the configuration: 1s2 2s2 2p6 3s2 3p6 4s1 3d5, not 1s2 2s2 2p6 3s2 3p6 4s2 3d4
The reason for this is basically to do with achieving a higher level of stability within the atom
http://www.chemguide.co.uk/atoms/properties/atomorbs.html#top
The advice from lucyhol1012 is brilliant, but just to add to the confusion(!) there is exceptions to the rule of filling up shells that you will probably need to know for the exam:
Copper and chromium do not follow the general rule for filling up shells.
Copper has the configuration: 1s2 2s2 2p6 3s2 3p6 4s1 3d10, not 1s2 2s2 2p6 3s2 3p6 4s2 3d9
Chromium has the configuration: 1s2 2s2 2p6 3s2 3p6 4s1 3d5, not 1s2 2s2 2p6 3s2 3p6 4s2 3d4
The reason for this is basically to do with achieving a higher level of stability within the atom
EierVonSatan
Mg at GCSE is 2,8,2
which is more precisely {1s2,}, {2s22p6},{3s2}
which is more precisely {1s2,}, {2s22p6},{3s2}
Right thankyou I understand!
So what is the thing with the box and 2 arrows facing up and down?
I have a worksheet to do and it has lots of little boxes
bob9001
Right thankyou I understand!
So what is the thing with the box and 2 arrows facing up and down?
I have a worksheet to do and it has lots of little boxes
So what is the thing with the box and 2 arrows facing up and down?
I have a worksheet to do and it has lots of little boxes
they are representations of orbitals - each box (orbital) can have 2 electrons, one arrow going up (spin up) and one arrow down (spin down)
for example sulfur 1s2 2s2 2p6 3s2 3p4
|up,down| - |up,down| - |up,down||up,down||up,down| - |up,down| -|up,down||up, nothing||up, nothing|
They are half-arrows, and each half-arrow is one electron. They form an electron pair, and they go into a box together. Only one pair goes into each box. You fill them in order of energy level.
bob9001
Right thankyou I understand!
So what is the thing with the box and 2 arrows facing up and down?
I have a worksheet to do and it has lots of little boxes
So what is the thing with the box and 2 arrows facing up and down?
I have a worksheet to do and it has lots of little boxes
Thats a way of illustrating the electrons. One box with two arrows means two electrons. You always fill all the boxes up with one electron facing up first, then add the second facing down starting from the first box in that suborbital.
They just signify the electron arrangement.
You fill the boxes according to the arrangement.
Take this as the arrow |
1s2 2s2 2p6 3s2....
||
|| || || ||
| | |
You fill the boxes according to the arrangement.
Take this as the arrow |
1s2 2s2 2p6 3s2....
||
|| || || ||
| | |
EierVonSatan
they are representations of orbitals - each box (orbital) can have 2 electrons, one arrow going up (spin up) and one arrow down (spin down)
for example sulfur 1s2 2s2 2p6 3s2 3p4
|up,down| - |up,down| - |up,down||up,down||up,down| - |up,down| -|up,down||up, nothing||up, nothing|
for example sulfur 1s2 2s2 2p6 3s2 3p4
|up,down| - |up,down| - |up,down||up,down||up,down| - |up,down| -|up,down||up, nothing||up, nothing|
deadgenius
They are half-arrows, and each half-arrow is one electron. They form an electron pair, and they go into a box together. Only one pair goes into each box. You fill them in order of energy level.
Thankyou!
That has helped a lot
I am now going to attempt this worksheet!
everybody loves electronic configurations
scaryhair
Thats a way of illustrating the electrons. One box with two arrows means two electrons. You always fill all the boxes up with one electron facing up first, then add the second facing down starting from the first box in that suborbital.
lucyhol1012
They just signify the electron arrangement.
You fill the boxes according to the arrangement.
Take this as the arrow |
1s2 2s2 2p6 3s2....
||
|| || || ||
| | |
You fill the boxes according to the arrangement.
Take this as the arrow |
1s2 2s2 2p6 3s2....
||
|| || || ||
| | |
The diagrams helped a lot
So when you are filling up the subshells- do the electrons fill s orbitals first, then p orbitals then the other ones (d?) ?
That's because Chemistry is fun
And who doesn't love a bit of basic foundation chemistry. Haha!
And who doesn't love a bit of basic foundation chemistry. Haha!
Related discussions
- Help with AS level chemistry question
- Atomic Subshells
- A-Level Chemistry HELP !!!
- A level chemistry
- Dative or coordinate bonding URGENT
- how do you work out if soemthing has a vacant orbital for dative bonding
- Atomic Structure - Shapes of S and P orbitals AQA a level chem
- A level chemistry questions
- Group number correspondence on periodic table
- P orbitals A-level Chemistry
- Chemistry OCR A
- Chem question: How many orbitals are occupied in a silicon atom?
- should I choose A level chemistry
- Ask Us Anything!
- Chem a level
- Urgent a level chem help!!!
- A-level complex Dot and Cross diagrams
- Electron Configuration of Zinc (Zn)
- A level chemistry question
- Chemistry A level basics need help
Latest
Trending
