The word catalysing is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 19
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (21 words)
against, alicant, analyst, anglist, casting, gainsay, glycans, lacings, lasting, nastily, saintly, salting, satanic, scaling, scantly, slating, slaying, stagily, staying, stygian, styling