Explanation:
1. Electrons surround the nucleus in defined regions called orbits.
2. The shells further away from the nucleus are larger and can hold more electrons.
3. The shells closer to the nucleus are smaller and can hold less electrons.
4. The closest shell (closest to the nucleus) can hold a maximum of two electrons.
5. Once the first shell is full, the second shell begins to fill. It can hold a maximum of eight electrons.
6. Once the second shell is full, the third shell begins to fill.
7. Once the third shell contains Eighteen electrons, the fourth shell begins to fill.
8. The arrangement of electrons in shells around the nucleus is referred to as an atom's electronic configuration.
Answer:
For O: atomic number = 8 # neutrons = 8
For Al: atomic mass = 27, # electrons = 13
Answer:
There is a basic difference, because mass is the actual amount of material contained in a body and is measured in kg, gm, etc. Whereas weight is the force exerted by the gravity on that object mg. Note that mass is independent of everything but weight is different on the earth, moon, etc.
I think the answer would be 1.58 g.
