need Help Block of Asset

I don't think capital gains is attracted in this case.

Capital gains would have been attracted had the block of assets become empty.

Don't remember the provisions very clearly though 

  There is no capital gain in this case , its only when all block of assets ceases to exists. 

agree with vinnzz

Capital gains will arise only in a situation where the consideration received is greater than the WDV of the block to which it pertains. Even if there is one rupee closing WDV in the block of assets cap gains will not be applicable.