What is the NMR splitting pattern for Butane?

[jsmith613]

Homework Statement

Butane, CH₃CH₂CH₂CH₃
has two proton environments
would the splitting be 3, 6 OR 3,4

Homework Equations

The Attempt at a Solution

The 3 splitting would be because the CH₃ group is next to a carbon with 2 hydrogens (n+1 --> 2+1 = 3)

Now the 6 would be because both CH₂ groups neighbour a CH₃ and CH₂ group. (n + 1 --> 5+1 --> 6)

The 4 would be because both CH₂ groups neigbhour a carbon with three hydrogens (n+1--> 4)
I am not sure if splitting is induced if two CHEMICALLY IDENTICAL groups are next to each other. I know splitting occurs if the neighbouring carbon contains hydrogens BUT IF THE TWO GROUPS ARE IDENTICAL X-CH₂-CH₂-X then would the splitting be 6 or would it be 4

thanks

 

[sjb-2812]

See perhaps http://u-of-o-nmr-facility.blogspot.com/2009/08/500-mhz-1-h-nmr-spectrum-of-butane.html