Thomson realized that the accepted model of an atom did not account for negatively or positively charged particles. Therefore, he proposed a model of the atom which he likened to plum pudding. ... Rutherford with the assistance of Ernest Marsden and Hans Geiger performed a series of experiments using alpha particles.
Answer:
Honestly makes no sense sorry :(
Explanation:
I can try though.. There are three types of selectivity possible for any synthesis: (i) Chemoselectivity is deciding which group reacts. (ii) Regioselectivity is where the reaction takes place in that group. (iii) Stereoselectivity is how the group reacts with respect to the stereochemistry of the product.
A stereospecific mechanism specifies the stereochemical outcome of a given reactant, whereas a stereoselective reaction selects products from those made available by the same, non-specific mechanism acting on a given reactant. Of stereoisomeric reactants, each behaves in its own specific way.
I tried to explain it the best I could.
Hopefully this helps you :)
Feel free to correct me If it was wrong
Gravity. The rock is being pushed down and you are counteracting that force with a crowbar pushing it upward.
