Answer:
1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵
Explanation:
1) Ca:
Its atomic number is 20. So it has 20 protons and 20 electrons.
Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.
So, you have two more electrons (20 - 18 = 2) to distribute.
Those two electrons go the the orbital 4s.
Finally, the electron configuration is [Ar] 4s².
2) Pm
The atomic number of Pm is 61, so it has 61 protons and 61 electrons.
Pm is in the row (period) 6. So, the noble gas before Pm is Xe.
The atomic number of Xe is 54.
Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.
The resultant distribution for Pm is: [Xe]6s² 4f⁵.
On point? Do you have any options?
The cohesive forces between liquid molecules are responsible for the phenomenon known as surface tension<span>. I think the correct answer is option A. H2O will have the highest surface tension due to the hydrogen bonds that are present. Hope this answers the question. Have a nice day.</span>
Force is a strength or energy as an attribute or physical action or movement, motion is the action or process of moving or being moved
Answer:
A divergent boundary is when the plates move apart from each other. When the plates part, magma from under either plate rises and forms a volcano. A hotspot is the third place a volcano can form. This particular type is the least common.
Explanation:
