Gallum: Z = 31
electron configuration: [Ar] 4s^2 3d10 4s2 4p1
Highest energy electron: 4p1
Quantum numbers:
n = 4, because it is the shell number
l = 1, it corresponds to type p orbital
ml = may be -1, or 0, or +1, depending on space orientation, they correspond to px, py, pz
ms = may be -1/2 or +1/2, this is the spin number.
The average mass of an atom is calculated with the formula:
average mass = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2) + ... an so on
For the boron we have two isotopes, so the formula will become:
average mass of boron = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2)
We plug in the values:
10.81 = 0.1980 × 10.012938 + 0.8020 × mass of isotope (2)
10.81 = 1.98 + 0.8020 × mass of isotope (2)
10.81 - 1.98 = 0.8020 × mass of isotope (2)
8.83 = 0.8020 × mass of isotope (2)
mass of isotope (2) = 8.83 / 0.8020
mass of isotope (2) = 11.009975
mass of isotope (1) = 10.012938 (given by the question)
Answer:
It might cause fire or extreme smoke.
Explanation:
Break down the table into smaller sections. Memories period by period or if you like by group (like halogens or noble gases).
Just say the elements in order everyday 1-10 then when you get those 11-20 and continued.
