Which of the following statements about the periodic trend of atomic radius is/are true? i. atomic radius decreases from left to right across a period because zeff increases. ii. atomic radius increases from left to right across a period because the number of valence electrons increases. iii. atomic radius increases from top to bottom in a group because the number of electron shells increases. 1. i only 2. i and iii only 3. ii and iii only 4. ii only

2. I and III only

Explanation:

I. Atomic radius decreases from left to right across a period because Zeff increases.

Atomic radius decreases as we move from left to right because here the effective charge of the nucleus will attract the electron cloud due to which all electrons will come closer as we move from left to right

III. Atomic radius increases from top to bottom in a group because the number of electron shells increases.

As we move from top to bottom then due to increase in the number of orbitals the effective charge of the nucleus will decrease and hence the atomic radius will also increase

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

not copied too! hope this !

joke:

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