With a larger distance between the negatively-charged electron and the positively-charged nucleus, the force of attraction is relatively weaker. Therefore, electron affinity decreases. Moving from left to right across a period, atoms become smaller as the forces of attraction become stronger.
Does force of attraction increase across a period?
Across a period, the distance between the nucleus and the valence electrons remains constant but the effective core charge increases. As a result the force of attraction between the nucleus and the valence electrons increases across a period.
Does nuclear attraction increase across a period?
Across a period, effective nuclear charge increases as electron shielding remains constant. A higher effective nuclear charge causes greater attractions to the electrons, pulling the electron cloud closer to the nucleus which results in a smaller atomic radius.
How does Coulomb’s law affect periodic trends?
8.6 Periodic Trends in the Size of Atoms
According to Coulomb’s Law, the attraction is stronger as the charge on the nucleus (Z) increases, and as the electron gets closer to the nucleus.
Does Z effective increase down a group?
The effective nuclear charge, Zeff, increases down a group which draws electrons closer towards the nucleus, decreasing atomic radius.
What is a electrostatic attraction?
Electrostatic attraction is essentially the attraction between the positively charged nucleus of an atom and the negatively charged electrons surrounding it. The greater the positive charge of the nucleus (the more protons), the greater the effective nuclear charge.
Why does electron affinity increase across a period?
Electron affinity increases upward for the groups and from left to right across periods of a periodic table because the electrons added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons.
Does coulombic attraction increase across a period?
Effective nuclear charge increase more steadily going across a period (more protons but not more shells) than going down a group (more protons but also more shells).
Why does the electronegativity increase across a period?
Across a period from left to right the electronegativity of atoms increases. … As you move from left to right across the periodic table, atoms have a greater nuclear charge and a smaller covalent radius. This allows the nucleus to attract the bonding electrons more strongly.
How does Coulombic attractive forces affect ionization energy?
The greater the ionization energy, the more difficult it is to remove an electron. Using the same Coulombic attraction ideas, we can explain the first ionization energy trends on the periodic table. … The greater an atom’s electronegativity, the greater is its ability to attract electrons to itself.
How does Coulomb’s law affect the size of an atom?
According to Coulomb’s Law, as the atomic number increases within a series of atoms, the nuclear attraction for electrons will also increase, thus pulling the electron(s) closer to the nucleus. … Such a relationship between atomic number and atomic radius is a direct correlation.
How does coulombs law affect atomic radius?
Atomic radius increases from top to bottom within a group because: There is bigger distance between the protons in the nucleus and the outer electrons, decreasing the attraction forces according to Coulomb’s Law.
Why does Z effective increase?
Where Zeff = effective nuclear charge, Z = Nuclear charge, σ = shielding constant. The effective nuclear charge increases from left to right along a period because the repulsive forces among the electrons is less than the attractive force exhibited by the added proton.
Why does ionic radius decrease across a period?
Ionic radius decreases moving from left to right across a row or period. More protons are added, but the outer valence shell remains the same, so the positively charged nucleus draws in the electrons more tightly. … While the atomic radius follows a similar trend, ions may be larger or smaller than neutral atoms.
Why atomic radius decreases across a period?
Within a period, protons are added to the nucleus as electrons are being added to the same principal energy level. These electrons are gradually pulled closer to the nucleus because of its increased positive charge. Since the force of attraction between nuclei and electrons increases, the size of the atoms decreases.