<h3>
Answer:</h3>
Al- [Ne] 3s²3p¹
As- [Ar] 4s²3d¹⁰ 4p³
Explanation:
- Electron configuration of an element shows the arrangement of electrons in the energy levels or orbitals in the atom.
- Noble-gas configuration involves use of noble gases to write the configuration of other elements.
- This is done by identifying the atomic number of the element and then identifying the noble gas that comes before that particular element on the periodic table.
- Aluminium: The atomic number of Al is 13. The noble gas before Aluminium is Neon which has 10 electrons. Therefore the remaining 3 electrons fills up the 3s and 3p sub orbitals.
- Thus, the noble-gas configuration of Al is [Ne] 3s²3p¹
2. Arsenic, Atomic number is 33
- Noble gas before Arsenic is Ar,. Argon has 17 electrons, then the remaining electrons fills up the 4s, 3d and 4p sub-orbitals.
- Thus, the noble-gas configuration of As is [Ar] 4s²3d¹⁰ 4p³
Yes. If this is the balanced equation:
AlCl3 + 3Na —— 3NaCl + Al
then Al was reduced from a 3+ oxidation (to neutralize the 3- from the chlorine) to a 0 oxidation (elemental ground state).
Answer:
pH = 12.52
Explanation:
Given that,
The [H+] concentration is 
.
We need to find its pH.
We know that, the definition of pH is as follows :
![pH=-log[H^+]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%2B%5D)
Put all the values,
![pH=-log[3\times 10^{-13}]\\\\pH=12.52](https://tex.z-dn.net/?f=pH%3D-log%5B3%5Ctimes%2010%5E%7B-13%7D%5D%5C%5C%5C%5CpH%3D12.52)
So, the pH is 12.52.
