Given word is CHASM
Letters are {A,C,H,M,S}
Number of word starting with A is 4!=24
Then, the next word starts with
CA _ _ _.
The remaining 3 letters can be rearranged in 3!=6 ways.
The next word is
CHAMS
Then
CHASM
Therefore, the rank of CHASM is 24+6+2=32