Why does atomic size increase going down?

Why does atomic size increase going down?

Atomic size increases as you go down a column because of the addition of another electron shell and electron shielding. Atomic size decreases as you go right across a row because of increased protons.

Why does atomic size decrease across a period class 11?

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.

Why the atomic size decreases across the period & increases down the group explain by taking examples?

As we move along a period from left to right in the periodic table, number of shells remains the same while nuclear charge increases by one at each step. However, this effect of increase in the number of shells dominates over increase in nuclear charge. As such, atomic size increases down a group in the periodic table.

Why does atomic size tend to decrease with increasing atomic number across a row of the periodic table?

As the atomic number increases along each row of the periodic table, the additional electrons go into the same outermost shell, causing the atomic radius to decrease due to the increasing nuclear charge.

Why does the atomic radius decrease across Period 3?

Going across period 3: the number of protons in the nucleus increases so … therefore the force of attraction between the nucleus and the electrons increases … and the atomic radius decreases.

What makes up the size of an atom?

Atomic size is the distance from the nucleus to the valence shell where the valence electrons are located. The separation that occurs because electrons have the same charge. The number of protons in the nucleus. The core electrons in an atom interfere with the attraction of the nucleus for the outermost electrons.

How does the atomic size vary in a group and across a period explain with suitable example?

Across the period from left to right there is a decrease in atomic size with increase in nuclear charge of the element. Atomic size increases down the group because of the addition of extra shells. So, as we move from group 1 to group 18 the size of the atom will decrease due to increased effective nuclear charge.

Does atomic size increase/decrease or remains the same as you go across period 2 explain why?

Atomic size gradually decreases from left to right across a period of elements. This is because, within a period or family of elements, all electrons are added to the same shell.

Why does atomic radius decrease across a row?

What affects atomic size?

There are three factors that help in the prediction of the trends in the Periodic Table: number of protons in the nucleus, number of shells, and shielding effect. The atomic size increases from the top to the bottom in any group as a result of increases in all of the three factors.

Why does atomic size decrease along the period of a period?

Along the period, atomic size decreases due to an increase in effective nuclear charge. This means that though the number of protons keeps increasing in the nucleus, the electrons are added to the same shell.

Why does the size of an atom increase down a group?

The size increase because the effective nuclear charge (positive charge of nucleus) experienced by the outer electrons decreases down a group. Effective nuclear charge decreases because the inner electrons repel the outer electrons, weakening the nucleus pull for the outer electrons.

Why does the number of protons in the nucleus change across periods?

This is a very important periodic phenomenon: the contraction of atomic radii across the period. While as we add to Z (the number of protons in the nucleus), we also add another electron (and charge is therefore kept neutral), the increased nuclear charge acts disproportionately on the valence electrons, and contracts this shell.

What happens to atomic radii down a group?

What happens to atomic radii down a Group? Atomic radius decreases across a period because valence electrons are being added to the same energy level at the same time the nucleus is increasing in protons. The increase in nuclear charge attracts the electrons more strongly, pulling them closer to the nucleus.