Are hair straighteners a physical or a chemical change?

Hair straighteners, like perms, are chemical.

They break disulphide bonds between hair protiens, then reform them when the the hairs are straight, at the end of the process.

Straightening with just water only breaks and reforms the hydrogen bongs in hair, making it much less 'permanent'.

Are hair straighteners a physical or a chemical change?

physical

Are hair straighteners a physical or a chemical change?

chemical

Are hair straighteners a physical or a chemical change?

Depends on what kind of straightner you have. Flat irons are physical, perms are chemical.