Piano B7 Chord
B7 is a common 7th chord. Click here to read about 7th chords if you haven't read this page yet and get back here once you're done. I'm sure you'll find it more useful to understand the conecpt of creating every 7th chord instead of just one at a time.
Look at the image to see how to play B7 in the root position on piano.
You should basically play the notes B (Right below middle C) D#, F# and A with the 1st, 2nd 3rd and 5th fingers.
The meaning of a chord in the root position is that the key note of the chord (B in our case) is placed as the lowest note of the chord.
The B7 chord functions mostly as a Dominant Chord for a E Major Chord. It means that this chord contains a lot of tension which needs to be solved to the Tonic which functions as the Release chord (home chord). You can learn more about it in Here.
If you're not sure whether you got it right check out the musical intervals you created. The B7 chord is made out of a major third which defines it as a major chord, then two minor third on top of each other.
Another way to build this chord quickly is by building a B Major chord and adding a minor third on top of the F# note, or adding a whole tone under the key note (B) which will create a B7 chord in the 3rd inversion (All possible chord inversions are given below in this page).
Now let's invert B7 into all possible Chord Inversions (So the key note of the chord will appear in different places of the chord). The possible chord inversions are given in the image.
So when we'll see the chord symble B7 above a bar it means we have to play a B7 chord.