Answer: a) 
b) 
c) 
d) 
Explanation:
General representation of an element is given as:_Z^A\textrm{X}
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
In an atom, when neutrons or protons are lost or gains, it directly affects the mass number of an atom.
Atomic number is defined as the number of protons or number of electrons that are present in an atom.
It is characteristic of a particular element.
Atomic number = Number of electrons = Number of proton
a) Z 74, A 186:
b) Z 80, A 201:
c) Z 34, A 76:
d) Z 94, A 239.:
Seismic waves hope this helps.
6+2=115 and its good it took test
Atom is a neutral element found in nature without any charge. In other words, it has same number of Protons and electrons, whereas ion is a charged thing, either positive or negative. We can find their charge by:
Charge = Number of Protons - Number of Electrons
Hope this helps!
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
