Rust forming on a piece of iron is an example of which of the following? * 1The natural process of decay as metallic ions age
2 A physical change because the process can be reversed
3 A chemical change because oxygen atoms from the atmosphere bonded with the iron atoms
4 A violation of the laws of physics because new mass has been created​

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

Calculate the ratio of h+ ions to oh– ions at a ph = 7. find the concentration of h+ ions to oh– ions listed in table b of your student guide. then divide the h+ concentration by the oh– concentration. record this calculated ratio in table a of your student guide. compare your approximated and calculated ratios of h+ ions to oh– ions at a ph = 7. are they the same? why or why not? record your comparison in table a. what is the concentration of h+ ions at a ph = 7? mol/l what is the concentration of oh– ions at a ph = 7? mol/l what is the ratio of h+ ions to oh– ions at a ph = 7? : 1

George is a dalmatian puppy. describe what happens to light that allows you to see george’s black and white coat.