The remains of an animal or plant preserved within a layer of rock I think I’m sorry if I’m wrong
Answer:
the properties of three undiscovered elements is the correct answer.
Explanation:
After he completed his work Mendeleev predicted the properties of the undiscovered elements.
In the year 1871, Dmitri Mendeleev predicted the detailed existence and the properties of the three elements that are undiscovered and he gained tremendous fame.
He left the gap in the table to put the elements which are not identified at that time and by glancing at the physical and chemical properties of an element next to the gap, Mendeleev could predict the properties of the not discovered elements.
Answer:
1) 8 valence electrons are a full shell that makes the atom more stable.
Explanation:
Due to the octet rule, atoms tend to form compounds in ways that give them eight valence electrons and thus give them the electron configuration of a noble gas, making them stable.
Answer:
The element with electron configuration 1s² 2s² 2p⁶ will most likely not react with an element having seven Valence electrons.
The electron configuration of the element in discuss is 1s² 2s² 2p⁶.
The element has enough electrons to fill it's energy level, n = 2 shell.
In essence, the element in discuss is unreactive as it has attained it's octet configuration and as such is neither in need of an electron nor ready to donate an electron.
As such, although an atom having seven Valence electrons is highly electronegative and as such is an electron attractor, the element with the full octet configuration does not react with it.
This unreactive nature of noble gases is attributed to the full octet configuration of noble gases.
P.S: The electron configuration above is the electron configuration of Neon, Ne.
Haber's process is used for the industrial production of ammonia. The process conditions at which maximum yield can be obtained, include 15-20mPa pressure, 400-500 degrees Celsius of the temperature, use of methane as a source of hydrogen, use of iron-based catalysts and combined with K2O, CaO, SiO2, and Al2O3<span>. Reuse of unreacted gases can lead to the achievement of 97% yield. </span>
