The rusting of iron is not a physical property because A. the identity of iron remains unchanged
B. a new substance with new properties formed
C. iron is magnetic
D. it cannot be observed

The answer to this is the 3rd choice!

Self-ionizes to form an equilibruium system in which [ h_{3} o^{+} ]=[ oh^{-} ]=10^{-7} m

Hello! mitosis and meiosis are the same, because they are both ways of dividing cells and reproducing cells. they are different in many ways, but the main one is that meiosis splits the number of chromosomes in 1/2, while the number of chromosomes remains the same for mitosis. plus, meiosis has two stage of division, unlike mitosis, where it has only one.