11. I would say physical because the color of the item is changed and the texture and density is changed aswell.
Answer: Rotation occurs at single bonds that are sigma bonds. Rotational barrier is the amount of activation energy required to covert rotamer to another by rotation that occurs around the sigma bond(C-C single bond). Due to the presence of steric hindrance that is the nonbonding interaction effects the reactivity of ions and molecules, activation energy increases. So the rotational barrier in butenyl cation is high.
Its B and D
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F- is the smallest because it accepts 1 electron 2 make its atomic number 10 making it have jst 2 orbitals but O²-,N³- and Na have their atomic number to be 18,17 and 11 respectively with 3 orbitals..
hope this helps *winks*
