The gold foil experiment by Ernest Rutherford proved that the positive charge of an atom is located in the nucleus, the small region that contributes most to the mass of the atom. Most of the atom is empty space, but the nucleus, however small, dictates the mass of the atom.
The formula for aluminum fluoride is 
That means that there is 1 Aluminum and 3 fluorde ions in 1 molecule. The 3 does not effect the Aluminum at all.
The Answer is A
The higher the slope of a ramp the more velocity and speed the marvel will gain, which means more distance traveled
Answer: Noble-gas notation of Sn contains Kr.
Explanation: Tin ( Sn) is an element having atomic number 50.
Nearest noble gas to this element is Krypton which has an atomic number 36.
Electronic configuration or noble-gas notation for Sn is written as :
![Sn=[Kr]4d^{10}5s^25p^2](https://tex.z-dn.net/?f=Sn%3D%5BKr%5D4d%5E%7B10%7D5s%5E25p%5E2)
As seen from above, Noble gas Krypton having symbol 'Kr' is coming in the electronic configuration for Tin.
Answer: A
The protons in the nucleus repel each other
Explanation:
the number of protons inside a nucleus increases the electrostatic repulsion between protons increase reducing the binding energy. Thus the electrostatic force determines the stability of a nuclear configuration