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The amount of valence electrons in an atom of an element is the amount of electrons placed at the outermost ring of the atom.

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โˆ™ 2010-01-11 00:50:16
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Q: How do you know how much valence electron an element has?
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What is the relationship between an element's number of valence electrons and its reactivity?

When we say valence electron we mean the number of electron left it the outermost shell of element, valence electron can be positive of negetive. If an element need much electrons to be octet, that means that the element is not reactive than the one who will give out electrons, the the one who can give electrons much are less reactive than the one who can give a litle and the reaction will be normal as it is soppused to be, Eg lithium and berylium. Lithium is more reactive than berylium because lithuin has 1valence electron while berylium has 2....reactivity goes with the action of valence electron in an element

Why is so much emphasis placed on valence electrons?

The valence electrons of an element are mainly what determine an element's properties.

How much valence electrons does sulfur have?

The element Sulfur has 6 valence electrons. : )

Which element is less reactive an element whose atom have seven valence electrons or an element whose atom have eight valence electrons?

An element whose atoms have eight valence electrons each is much less reactive, because such an element already has the energy-minimizing electron configuration, a closed octet, that other elements achieve by reaction with one another. Elements with seven electrons in each valence shell have a strong drive to abstract another one from a less electronegative atom such as a metal.

Why is much more energy needed to remove the third electron than the second in magnesium atom?

magnesium has a 2 valence electrons. because the third electron is not a valence electron, or in the outer shell, much more energy would be needed to remove it

Which element has the same valence electron configuration as phosphorus?

Pretty much any element in group 15 (N, P, As) will have 2 "s" electrons and 3 "p" electrons in their valence shells, it's just that they will at different energy levels. For example, N is 2s2 2p3 and P is 3s2 3p3.

Why does ionization energy increase as atomic radius decreases?

Ionization energy is how much energy is needed to remove an electron from the valence shell (the outermost shell). When the atomic radius is smaller, you will need more energy to remove an electron because the pull from the nucleus on the electron is stronger. If the atomic radius is larger, then it will be much easier to remove an electron from the valence shell because there are more layers (shieldings) between the nucleus and valence shell.

Which things determine an element's electronegativity?

the number of valence electrons in the atom's outer shell how much the valence electrons are shielded from the nucleus

Why is the first ionisation energy of magnesium greater than that of sodium?

About twice as large, which is not that much at the first ionization level. Still, Magnesium has a slightly larger, one proton nucleus and one more electron in that valence level to add to the energy needed to pill the first electron out of it's orbital. Electron shielding may have something to do with this also as the other valance electron of this 2+ element may shield the pulled electron.

Why does having a low amount of electrons in the valence shell make an element reactive?

Well, either a high amount or a low amount. Take the alkali metals for example. They all have just one valence electron and they need to lose it to fulfill the octet rule. That is what makes them so reactive; they will combine with any element in order to lose that one electron. They all have a low ionization energy, meaning it takes a relatively small amount of energy to knock off that lone electron, whereas other elements have to lose more electrons. This also applies to elements with a lot of valence shell electrons, such as fluorine which only needs one more electron to fulfill the octet rule. This is another element that will react with almost anything because it doesn't take much for it to "get what it wants".

Why does a potassium atom always lose its one valence electron what type of bond will it form with a chlorine atom?

A potassium atom "always" loses exactly one valence electron when it reacts with another element, because one valence electron in a potassium atom has a much lower ionization energy requirement than any other electron in the same atom. (This property is generally ascribed to the fact that when a potassium loses exactly one electron, it acquires the very stable electron configuration of the noble gas argon.) A chlorine atom has a very strong attraction (its electronegativity) for exactly one electron, which gives the charged atom the electron configuration of an argon atom. Therefore, when a potassium atom is close enough to a chlorine atom, one electron is transferred between to form an ionic bond and a formula unit of the compound potassium chloride.

Is chlorine a metal or nonemetal?

Chlorine is a nonmetal. It is only one electron short of a noble gas electron configuration and is much more likely to abstract an electron from some other element than to donate one to some other element.

How many additional valence electrons does flurine need to have a full valence shell?

I believe you are talking about fluorine. If you are, F needs one more electron to gain a full shell.If you go to WikiAnswers for this information, that is counterproductive, because there is a much better way to do it. Look at the periodic table. Groups IA through VIIIA tell you what you need to know. IA has one valence electron, IIA has two valence electrons etc. Fluorine is in group VIIA and therefore has seven valence electrons. All atoms want eight, and thus fluorine is in need of one more.

What can be added to an atom to cause a nonvalence electron in the atom to temporarily become a valence electron?

The question is: What can be added to an atom to cause a nonvalence electron in the atom to temporarily become a valence electron?This question may seem hard and/or confusing, but it's really not. You just have to think about it for a minute. This question was in my science quiz online. I had to take LOTS of notes, and guess what?, the answer was right there in my notes..The notes that I took for this question had the topic:Electrons in an ElementMy notes were:-Electrons occupy the electron cloud.-Each electron occupies an energy state.-Electrons farther from the nucleus occupy a higher energy state.-The electron cloud is divided into energy levels.-Each energy level can hold a certain number of electrons-Valence Electrons are usually found in the highest energy level.Not very much notes, but lots of information, and most of them are about energy, and one is about Valence electrons. So, let's figure this.If a valence electron usually have the highest energy level, then a nonvalence electron must not have any energy levels. So, what you would have to add to the nonvalence electron is add energy to become a valence electron.Our question is: What can be added to an atom to cause a nonvalence electron in the atom to temporarily become a valence electron?So the answer to our question is: Energy. Energy can be added.

What can you determine about an about an element if you only know its group number on the periodic table?

The group number tells you the number of valence electrons. In a sense, this also tells you much about how it will react and how it may form compounds with other elements.

Which group of elements is the most active and why?

The alkali metals, group one on the periodic table. Starts with Lithium (Li) and ends with Francium (Fr). Or at least until Ununnunium is discovered, as it will be thenext alkali metal. The reason for their high reactivity is that they have only one valence electron. Valence electrons are the electrons that are involved in forming bonds with other elements. With only one valence electron, the atomic radius (how far away from the nucleus electrons can travel) is at its largest, making it so much easier for the electron to be taken by an other element that needs one valence electron, such as Chlorine (Cl). The reason that it is hard to find pure Sodium (Na) in nature is because it is an alkali metal, and therefore tends to bond with other elements rather than be alone.

What makes fluorine the most reactive element?

Atoms want to have a full outer shell of electrons as this is energetically favorable. Fluorine only needs one to complete its shell. All the halogens do likewise. With fluorine however, the valence electrons are much closer to the nucleus than chlorine, bromine, iodine or astatine. This means there is a stronger pull on electron joining the other valence electrons. This makes fluorine the most reactive element. For the exact reverse reasons francium is the most reactive metal and would react explosively with fluorine. It has only one electron to lose and that electron is a long way from the nucleus. This makes the hold on the electron weak and it is easily lost and hence extremely reactive.

How is the electron configuration of Sulfur consistent with the formation of Na2S and SF6?

Sulfur has six valence electrons and can therefore attain an inert gas configuration in two different ways: by accepting two electrons to attain the electron configuration of argon or donating or sharing six electrons to attain the electron configuration of neon. In combination with the much less electronegative element sodium, sulfur accepts one electron from each of two sodium atoms to form the ionic compound Na2S, but in combination with the more electronegative element fluorine, sulfur shares its six valence electrons with each of six fluorine atoms to form six polar covalent bonds with fluorine.

Why is caesium more reactive than sodium?

Caesium's single outer electron is much further from the nucleus than that of sodium, so caesium loses its valence electron much easily than sodium, therefore caseium is much more reactive than sodium.

Why is it difficult to remove an electron from halogens?

In their outer electron shell, halogens have 7 valence electrons, one less than the number needed for a full shell. Therefore, it is much, much easier for the halogen to gain an electron in bonding than for it to lose 7 - the ionization energy (energy required to remove an electron from an atom) is quite high.

Why electron affinity of fluorine is large?

Electron affinity of an element is defined as the energy released by adding an electron to a gaseous atom of the element. With the electronic configuration of the fluroine atom being [Ne] 2s2 2p5, it needs just one more electron to form the fluoride ion (F-) which has the noble gas structure and is much more stable.

How is an atom of the element sodium structurally different from an atom of magnesium?

A sodium atom has 11 protons and 11 electrons including 1 outer shell electron A magnesium atom has 12 protons and 12 electons of which 2 are in the outer shell. Sodium loses its valence electron more easily than magnesium does, making the sodium much more reactive.

How do you find the second ionization energy of an element?

In general, you can pretty much predict that the second ionization energy will always be higher than the first ionization energy regardles of what atom you are looking at. This is because when you remove an electron, there is less electron-electron repulsion in the valence shell, which means that the electron cloud shrinks a bit. When it shrinks, the average distance from the nucleus for the remaining valence electrons decreases, increasing the amount of energy needed to remove them. This effect is magnified TREMENDOUSLY if you are looking at the group 1 elements (alkali metals), because after ionizing the first electron you remove a shell. This means that the valence shell is now closer to the nucleus and the effective nuclear charge that those valence electrons feel is increased. For instance, as a result, the 2nd ionization energy is very high. In the case of Na+, the 2nd ionization energy is higher than even helium, the atom that has the highest first ionization energy on the periodic table.

Why do the elements in the group 1 and 2 react with group 17?

The group 1 and 2 elements have much lower electronegativity value than group 17 elements and therefore lose electrons to the group 17 elements. The group 17 elements require only one more electron to have a full valence shell and thereby acquire the stable electron configuration of the next higher atomic number noble gas. The group 1 and 2 elements achieve a stable electron configuration when they lose all their outermost (valence) electrons and thereby acquire the electron configuration of the next lower atomic number noble gas. One group 1 element will combine with one group 17 element and one group 2 element will combine with two group 17 elements. Examples include NaF, and MgCl2.

How much does the element titanium cost?

I don't know..... shittt