STOCKHOLM—The Royal Swedish Academy of Sciences will announce the winners of the 2012 Nobel Prize in chemistry on Wednesday, capping this year's science awards before the Nobel spotlight moves to literature and peace.

Like the other science awards, the chemistry prize normally rewards research done more than a decade ago so the judges have plenty of discoveries to choose from.

The Nobel week started Monday with the medicine prize going to stem cell pioneers John Gurdon of Britain and Japan's Shinya Yamanaka. Frenchman Serge Haroche and American David Wineland won the physics prize Tuesday for work on quantum particles.

The Nobel Prizes were established in the 1895 will of Swedish industrialist Alfred Nobel, the inventor of dynamite. Each award is worth 8 million kronor, or about $1.2 million.