# Question: Why Is The Number Of Electrons In The Outermost Shell Important?

## Why is 3rd shell 8 or 18?

The third shell of an atom has 18 electrons only not 8 electrons.

You might be confused because first the electrons of 4s are filled and then the 10 electrons of 3d shells are filled.

They are filled because of the n-l rule.

So after filling the 3s and 3p subshell with 8 electrons, the next shell to fill is the 4s one..

## What is special about valence electrons?

Valence electrons are the outermost electrons in an atom. Thus, they require less energy to remove than electrons at lower energy levels (if any). Also, they are the electrons that neighboring atoms will interact with.

## How many valence electrons are there in an atom of oxygen?

six valence electronsOxygen has six valence electrons in its elemental form so its formal charge is 6 – 6 = 0.

## Why are the outermost electrons important?

The electrons that occupy the outer most shell of an atom are called valence electrons. They are important because they determine how an atom will react. By writing an electron configuration, You’ll be able to see how many electrons occupy the highest energy level.

## What is the importance of 8 valence electrons?

The octet rule refers to the tendency of atoms to prefer to have eight electrons in the valence shell. When atoms have fewer than eight electrons, they tend to react and form more stable compounds.

## What is an electron dot diagram?

A Lewis electron dot diagram (or electron dot diagram or a Lewis diagram or a Lewis structure) is a representation of the valence electrons of an atom that uses dots around the symbol of the element. The number of dots equals the number of valence electrons in the atom.

## Where are electrons located?

Unlike protons and neutrons, which are located inside the nucleus at the center of the atom, electrons are found outside the nucleus. Because opposite electric charges attract each other, negative electrons are attracted to the positive nucleus.

## Why can’t atoms only have 8 valence electrons?

This is because of the quantum nature of the atoms, where electrons are organized in shells: the first (named the K shell) has 2 electrons, the second (L-shell) has 8, the third (M shell) has 18. Atoms combine into molecules by trying in most cases to have valence electrons entirely filling a shell.

## How do I find number of electrons?

The number of protons, neutrons, and electrons in an atom can be determined from a set of simple rules. The number of protons in the nucleus of the atom is equal to the atomic number (Z). The number of electrons in a neutral atom is equal to the number of protons.

## What is a valence electron and why is it important?

Valence electrons are the electrons in the outermost energy level of an atom — in the energy level that is farthest away from the nucleus. Being able to determine the number of valence electrons in a particular atom gives you a big clue as to how that atom will react. …

## How many electrons are in the 5 shell?

Questions and AnswersEnergy Level (Principal Quantum Number)Shell LetterElectron Capacity3M184N325O506P722 more rows

## Why are there only 8 electrons in the outer shell?

The eight- electrons stability of an atom is stemmed from the stability of the noble gases or the elder name inert gases, which had long been known as unreactive or noble. … However, this rule is justified for elements of second row in the periodic table, which their outermost- shell capacity is 8 electrons.

## How many electrons are in the outermost shell?

eight electronsMost of the elements important in biology need eight electrons in their outermost shell in order to be stable, and this rule of thumb is known as the octet rule. Some atoms can be stable with an octet even though their valence shell is the 3n shell, which can hold up to 18 electrons.

## Where do electrons have the most energy?

nucleusThe energy of an electron depends on its location with respect to the nucleus of an atom. The higher the energy of an electron in an atom, the farther is its most probable location from the nucleus.

## Why are shells called KLMN?

The names of the electron shells come from a fellow named Charles G. … It is produced when an electron in the innermost shell is knocked free and then recaptured. This innermost shell is now called the K-shell, after the label used for the X-ray. Barkla won the 1917 Nobel Prize for Physics for this work.

## What is the maximum number of electrons in the 4th Shell?

32Thus, the fourth level can hold up to 32 electrons: 2 in the s orbital, 6 in the three p orbitals, 10 in the five d orbitals, and 14 in the seven f orbitals. The sublevels of the first four principal energy levels and the maximum number of electrons that the sublevels can contain are summarized in Table 5.1.

## How many electrons are in each shell?

Each shell can contain only a fixed number of electrons: The first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on. The general formula is that the nth shell can in principle hold up to 2(n2) electrons.

## What information is shown in an atom’s electron dot diagram?

Electron dot diagrams show the valence electrons for an atom. The dot diagrams are the same for each element in the representative element groups.

## Are electrons positive or negative?

Protons and Electrons A proton carries a positive charge (+) and an electron carries a negative charge (-), so the atoms of elements are neutral, all the positive charges canceling out all the negative charges. Atoms differ from one another in the number of protons, neutrons and electrons they contain.