there are 90 i believe
A key in piano is the black a or white object that can be pressed down to create sound. A key can also mean a certain number of notes that can be played together, creating a scale, cadence and arpeggios. When you talk about the key of a particular piece, if the piece has no sharps or flats, it in in the key of C Major or A Minor. (There are other modes, but I won't get into them.) If the key has flats, the Major key is a Minor fourth (6 half steps) down from the last flat, and the minor key is a minor third, 4 half steps below that. If the key has sharps, the Major key is one half step up from the last sharp, and the Minor key is a minor third 4 half steps below that.
There are two half-steps in the key of A: C# to D and G# to A
Any key on the standard keyboard is a tritone up from the key 6 half steps below, or down from the key 6 half steps above it. The basic fractional value is 7/5, but this represents 'just intonation', and in equal temperament the fractional value is not followed exactly.
There are two half-steps in the key of F: A to B flat and E to F
There are two half-steps in the key of D: F# to G and C# to D
a half step
The whole steps are like white-white-white but the half steps are white-blue-white. So as you can see two whole steps higher than G is B.
four whole steps away from the tonic note. ~Rae
The chromatic scale
Take a look at any keyboard. Each key is one half step away from the next. So if you were on an F#, a black key, and you moved up to the next white key, a G, you have gone one half step.
There are two half-steps in the key of b: D to E flat and A to B flat.
Each note in the scale must be moved up one whole tone. That is the distance of exactly two keys on the piano, regardless of color.