Which of the following is NOT a chemical change? rust forming on an iron fence

salt dissolving in a glass of water

using electricity to break down water into hydrogen and oxygen

Motivation cannot be developed with practice; a person either possesses it or they do not.

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

The peak wavelength for the blackbody curve of a star is in the uv range. assuming the radiation from this star can reach earth, would you be able to see it?