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.
Answer:
well they form by heat and pressure
Light energy is turned into chemical energy when <span>when a photochemically excited special chlorophyll molecule of the photosynthetic reaction center loses an electron, undergoing an oxidation reaction.
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Jupiter's atmosphere is composed predominantly of hydrogen and helium, but if you have to select any one option then we can look at the percentage of existence of these elements that would be
<span>90 percent hydrogen.
remaining 10 percent is helium
so choose Hydrogen.</span>
