Both, the reddish spots are rust and a chemical change. You will also find (after you have rubbed off the rust) that the surface of the knife is pitted. These pits are a physical changed caused by the chemical reaction.
The reddish-brown spots on your wet bread knife are likely due to oxidation, which is a chemical change. When metal, especially iron or steel, is exposed to moisture and oxygen, it can corrode and form rust, leading to those discolorations. This process alters the chemical composition of the metal, resulting in the formation of iron oxide, which appears as reddish-brown spots. Proper drying and maintenance of metal utensils can help prevent this unwanted chemical change.
The cast of You Forgot Me - 2007 includes: Victor Cekola Shannon Piper
The cast of Forgot Safety - 2003 includes: Geoff Nail Jason Stratton
The cast of He Forgot to Remember - 1926 includes: Clyde Cook Noah Young
The cast of The Woman Who Forgot Dinner - 2007 includes: Andrea Miltner as Woman
The cast of And Then They Forgot God - 1971 includes: Joseph Campanella Beverly Garland Adam West
The cast of Almost Forgot My Bones - 2004 includes: Tanya Evanson as Herself - Poet
The cast of They Forgot to Read the Directions - 1924 includes: Lord Beaverbrook as Jasper Habbakuk
The cast of Judy Forgot - 1915 includes: Marie Cahill as Judy Evans Sam Hardy as Freddy
The cast of Never Forgot - 2010 includes: Benjamin Farrar as Max Ashly Margaret Rae as Claire
The cast of So Funny I Forgot to Laugh - 2010 includes: Elizabeth Isibue as Michelle Reid
The cast of The Man Who Forgot - 1927 includes: William Hallam as Crazy Dan Walter Nicholls as Stephen Jackson