Answer: The energy of the 4-s subshell is lower than the energy of 3-d subshell.
Explanation:
During the filling of electrons in subshells, the lower energy levels are filled before the higher energy levels. Also known as Aufbau principle.
Energy of the sublevel = (n + l)
where : n = Principal quantum number
l = Azimuthal quantum number(s=0,p=1,d=2,f=3)
Energy of 4-s subshell= (4+0) = 4
Energy of 3-d subshell=(3+2) = 5
Energy of 4-s subshell is lower than the energy of 3-d subshell, that is why 4s orbital is filled before the 3-d subshell.
Answer:
0.095 moles of Calcium is there in 5.74 x 1022 atoms of calcium.
Explanation:
- As we know, 6.023*10^23 atoms of an element is equal to its atomic weight.
And, 6.023*10^23 atoms of an element is also equal to 1 mole of the element.
We have,
- 6.023*10^23 atoms of element calcium equals to 1 mole of Calcium
- 5.74*10^22 atoms of element calcium equals to
(1/(6.023*10^.23)) * 5.74*10^22 moles of calcium
Therefore,
- 5.74 x 1022 atoms of calcium= 0.095 moles of calcium.
Explanation:
The observable visible spectrum of Cr(acac)3 complex is different from that of
[Cr(en)3]Br3 due to strength of bonded ligand in the coordination sphere.
en is a strong field ligand compared to acac thus pairing occurs. In both the complexes
Cr is in +3 state, configuration [Ar] 3d^3. There are 3 unpaired e in Cr(acac)3 whereas 1 unpaired e in [Cr(en)3]Br3 due to pairing.
Answer:
option A is correct ( sodium, calcium and barium)
Explanation:
Given compounds:
Sodium chloride , calcium sulfide, barium oxide
We know that metals form positive ions. In order to solve the problem we must identify the metals from given compounds.
Na⁺Cl⁻
Ca²⁺S²⁻
Ba²⁺O²⁻
We can see that sodium, calcium and barium contain positive charges.
Thus option A is correct.
Because sodium have one valance electron. When it combine with chlorine sodium lose its one electron to complete the octet and chlorine accept it to complete its octet. Thus sodium form positive ion and chlorine form negative ion.
Similarly barium and calcium are present in group 2. Both have two valance electron. When they lose them cation are formed.
Other option are incorrect because,
Option B have sulfur and oxygen which are anion.
Option C have chlorine which is also anion
Option D have chlorine, sulfur and oxygen that are anions.
My educated guess should be the 3rd one
