Crossword and Su Doku

The winner of this month's crossword and Su Doku competitions will be published next month. The winners receive a £25 book voucher and a signed copy of Bill Bryson's A short history of nearly everything. Please send your completed entries to:

Chemistry World
Royal Society of Chemistry
Thomas Graham House
Science Park
Milton Road
Cambridge
CB4 0WF
UK

by 14 February.