The original (or at least the original I have) is in the key of F Major
[Intro]
Back-up vocals sing the first line in the song in the following manner:
F Bb C F
Take these chains from my heart and set me free
(the first F chord in that string of four is for the pick-up note where the girls sing a C note)
[Verse 1]
F C
Take these chains from my heart and set me free
C7 F
You've grown cold and no longer care for me
F7 Bb G7
All my faith in you is gone, but the heartaches linger on
C C7 F
Take these chains from my heart and set me free
[Verse 2]
F C
Take these tears from my eyes and let me see
C7 F
Just a spark of the love that used to be
F7 Bb G7
If you love somebody new, let me find a new love too
C C7 F
Take these chains from my heart and set me free
[Verse 3]
F C
Give my heart just a word of sympathy
C7 F
Be as fair to my heart as you can be
F7 Bb G7
Then if you no longer care for the love that's beating there
C C7 F
Take these chains from my heart and set me free