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How the effects of nuclear charge and the increasing number of core electrons in an atom oppose each other?
Wiki User
∙ 6y ago
The increasing number of core electrons serve to "shield" the outer electrons from the positive charges in the nucleus. Thus, the effective nuclear charge (Zeff) is reduced.
Wiki User
∙ 6y ago
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What is the effective nuclear charge for the atom Mg?
the effective nuclear charge on barium is 2.
What do mean by effective nuclear charge?
Effective nuclear charge is the net charge of an electron in an atom.Z(eff) = Z - S where:Z - atomic numberS - number of shielding electrons
What is charge effect?
the nuclear charge experienced by valence or outer-shell electrons, diminished by the shielding effect of inner-shell electrons and also by the distance from the nucleus
When electrons feel an increasing positive charge do they have a higher or lower energy?
lower energy
Why the 1st ionic energy increase across period 2?
Because as the nuclear charge increases, the attraction between the nucleus and the electrons increases and it requires more energy to remove the outermost electron and that means there is a higher ionization energy. As you go across the periodic table, nuclear charge is the most important consideration. So, going across the periodic table, there should be an increase in ionization energy because of the increasing nuclear charge.
How is the concept of effective nuclear charge used to simplify the numerous electron- electron repulsions in a many electron atom?
a) How is the concept of effective nuclear charge used to simplify the numerous electron-electron repulsions in a many-electron atom?Effective Nuclear Charge- the (net) positive charge experienced by an electron in a many electron atom. This charge is not the full nuclear charge. It accounts for the shielding of the nucleus by other electrons in the atom.The nucleus is surrounded by electrons. These electrons are shielded from the nucleus by electron repulsions. The effective nuclear charge is less than the actual nuclear charge because the repulsions of the electrons needs to be taken into account.This is done in the equationZeff = Z (protons) - S (screening constant, the inner core amount of electrons)b) Which experiences a greater effective nuclear charge in a Be atom, the 1s electrons or the 2s electrons?The 1s electrons would have a greater nuclear charge. The number of electrons between the 1s electrons and the nucleus is less than the number of electrons between the 2s electrons and the nucleus. This means the screening constant is larger. When you subtract the larger amount of electrons from the amount of protons, 4, the difference will be less, meaning the value of the effective nuclear charge will be less.
What is the effective nuclear charge for the atom Mg?
the effective nuclear charge on barium is 2.
Due to increasing nuclear charge the radii of the atoms decrease left to right across a period is that true?
yes that's true. as you go to the right in the periodic table you have more protons, but the number of energy shells remains the same so it pulls all the electrons close together (increasing nuclear charge) which decreases the atomic radius
What is the cause of lanthanide contraction?
The effect results from poor shielding of nuclear charge (nuclear attractive force on electrons) by 4f electrons; the 6s electrons are drawn towards the nucleus, thus resulting in a smaller atomic radius.In single-electron atoms, the average separation of an electron from the nucleus is determined by the subshell it belongs to, and decreases with increasing charge on the nucleus; this in turn leads to a decrease in atomic radius. In multi-electron atoms, the decrease in radius brought about by an increase in nuclear charge is partially offset by increasing electrostatic repulsion among electrons. In particular, a "shielding effect" operates: i.e., as electrons are added in outer shells, electrons already present shield the outer electrons from nuclear charge, making them experience a lower effective charge on the nucleus. The shielding effect exerted by the inner electrons decreases in the order s > p > d > f. Usually, as a particular subshell is filled in a period, atomic radius decreases. This effect is particularly pronounced in the case of lanthanides, as the 4f subshell which is filled across these elements is not very effective at shielding the outer shell (n=5 and n=6) electrons. Thus the shielding effect is less able to counter the decrease in radius caused by increasing nuclear charge. This leads to "lanthanide contraction". The ionic radius drops from 102 pm for cerium(III) to 86.1 pm for lutetium(III).
What is the effective nuclear charge of an atom primarily affected by?
inner electrons
What do mean by effective nuclear charge?
Effective nuclear charge is the net charge of an electron in an atom.Z(eff) = Z - S where:Z - atomic numberS - number of shielding electrons
What is charge effect?
the nuclear charge experienced by valence or outer-shell electrons, diminished by the shielding effect of inner-shell electrons and also by the distance from the nucleus
When electrons feel an increasing positive charge do they have a higher or lower energy?
lower energy
Why is a oxide ion larger than a oxygen atom?
In an oxide ion, electrons get added. This means, lesser nuclear charge. This is due to screening effect. The inner electrons shield the outer electron from the nuclear charge which is why the outer electrons get relatively lesser nuclear charge. So, more electrons means lesser nuclear charge. Consider a person standing in front of you. You get blocked from the view in front of you. Suppose two more people stand in front of you. Now, it is more difficult for you to catch a glimpse of the front view than it was before. This is exactly what happens in the oxide ion. Lesser nuclear charge means the electrons do not get pulled towards the nucleus as they were before, i.e., in the oxide ion, the electrons do not get pulled towards the nucleus as they were in the neutral oxygen atom.So, the electrons will be farther than they originally were.Thus, an oxide ion is larger than an oxygen atom.
Why is a oxygen ion larger than oxygen atom?
In an oxide ion, electrons get added. This means, lesser nuclear charge. This is due to screening effect. The inner electrons shield the outer electron from the nuclear charge which is why the outer electrons get relatively lesser nuclear charge. So, more electrons means lesser nuclear charge. Consider a person standing in front of you. You get blocked from the view in front of you. Suppose two more people stand in front of you. Now, it is more difficult for you to catch a glimpse of the front view than it was before. This is exactly what happens in the oxide ion. Lesser nuclear charge means the electrons do not get pulled towards the nucleus as they were before, i.e., in the oxide ion, the electrons do not get pulled towards the nucleus as they were in the neutral oxygen atom.So, the electrons will be farther than they originally were.Thus, an oxide ion is larger than an oxygen atom.
Why the 1st ionic energy increase across period 2?
Because as the nuclear charge increases, the attraction between the nucleus and the electrons increases and it requires more energy to remove the outermost electron and that means there is a higher ionization energy. As you go across the periodic table, nuclear charge is the most important consideration. So, going across the periodic table, there should be an increase in ionization energy because of the increasing nuclear charge.
As you move up to down in a column of the periodic table elements have what?
It increases because as you move down a family / column in a periodic table, the amount of protons and electrons increase, creating more rings of electrons on the atom, therefore with more rings, the size of the element increases.
