Answer:
- Option A): <em>Due to the constraints upton the angular momentum quantum number, the subshell </em><u><em>2d</em></u><em> does not exist.</em>
Explanation:
The <em>angular momentum quantum number</em>, identified with the letter l (lowercase L), number is the second quantum number.
This number identifies the shape of the orbital or <em>kind of subshell</em>.
The possible values of the angular momentum quantum number, l, are constrained by the value of the principal quantum number n: l can take values from 0 to n - 1.
So, you can use this guide:
Principal quantum Angular momentum Shape of the orbital
number, n quantum number, l
1 0 s
2 0, 1 s, p
3 0, 1, 2 s, p, d
Hence,
- <u>the subshell 2d (n = 2, l = 2) is not feasible</u>.
- 2s (option B) is possible: n = 2, l = 0
- 2p (option C) is possible: n = 2, l = 1
Answer:
it have 10 neutrons and it is Fluorine(F).
Answer:
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
Explanation:
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☃️ Chemical formulae ➝ 
<h3>
<u>How to find?</u></h3>
For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.

<h3>
<u>Solution:</u></h3>
Atomic weight of elements:
Ca = 40
C = 12
O = 16
❍ Molecular weight of 
= 40 + 12 + 3 × 16
= 52 + 48
= 100 g/mol
❍ Given weight: 10 g
Then, no. of moles,
⇛ No. of moles = 10 g / 100 g mol‐¹
⇛ No. of moles = 0.1 moles
☄ No. of moles of Calcium carbonate in that substance = <u>0.1 moles</u>
<u>━━━━━━━━━━━━━━━━━━━━</u>
Answer:
1. Lanthanum-139 atom is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.
2. In fact, over 80% of electric cars sold globally utilized permanent magnet-based motors in 2019. These magnets are typically made with rare-earth materials such as neodymium and dysprosium, which have a very geographically constrained supply chain.
3. It is the second most reactive of the rare-earth metals after europium. Lanthanum oxidizes in air at room temperature to form La2O3. It slowly reacts with water and quickly dissolves in diluted acids, except hydrofluoric acid (HF) because of formation of a protective fluoride (LaF3) layer on the surface of the metal.
Explanation: