- #1
jdoyle
- 7
- 0
The question in the attachment is from an old entrance exam for medical school. The correct answer is B.
I realize that if I assign a 'point value' to the levels of reactivity for each of the letters i.e. the more reactive the higher the number
T = 1
Q = 2
M = 3
J = 4
and that if the corresponding point value for the added element is less than that of the unknown element (letter) in the original molecule, then the reaction will not take place. For example
This reaction would not take place
MCl2 + T → TCl2 + M
because when substituting the point values for the two unknowns, the value of T<M.
3Cl2 + 1 → 1Cl2 + 3
On the other hand, the following reaction would take place because J>M
MSO4 + J → JSO4 + M
3SO4 + 4 → 4SO4 + 3
My problem is that I don't understand why. Is it because the addition of an element with a lower reactivity will not be able to break the bonds forming the original molecule? I would very much appreciate it if someone could give me an idiot-proof answeras I want to explain this to my daughter. Thanks in advance for your help.
John
I realize that if I assign a 'point value' to the levels of reactivity for each of the letters i.e. the more reactive the higher the number
T = 1
Q = 2
M = 3
J = 4
and that if the corresponding point value for the added element is less than that of the unknown element (letter) in the original molecule, then the reaction will not take place. For example
This reaction would not take place
MCl2 + T → TCl2 + M
because when substituting the point values for the two unknowns, the value of T<M.
3Cl2 + 1 → 1Cl2 + 3
On the other hand, the following reaction would take place because J>M
MSO4 + J → JSO4 + M
3SO4 + 4 → 4SO4 + 3
My problem is that I don't understand why. Is it because the addition of an element with a lower reactivity will not be able to break the bonds forming the original molecule? I would very much appreciate it if someone could give me an idiot-proof answeras I want to explain this to my daughter. Thanks in advance for your help.
John