Explanation: Helium has the smallest atomic radius. This is due to trends in the periodic table, and the effective nuclear charge that holds the valence electrons close to the nucleus. Atomic radius decreases as you move across a period from left to right and decreases as you move up a group from bottom to top.
Which element in group 1 has the smallest atomic radius?
Trends in Atomic Radius of Group 1 Elements
| name | atomic radius (pm) | Trend |
|---|---|---|
| lithium | 152 | smallest |
| sodium | 186 | ↓ |
| potassium | 425 | ↓ |
| rubidium | 244 | ↓ |
Which periodic group has the smallest atomic radius quizlet?
Silicon has the largest atomic number and therefore silicon has the smallest atomic radius because atomic radii decrease from left to right across a period.
Do noble gases have the smallest atomic radius?
Among Noble Gases, HELIUM has the smallest atomic radius. This is because of the reason that Atomic radii decreases along the period and increases down the group. Thus Noble gases being the last group, and among them HELIUM being the top-most element, it has the smallest atomic radius in noble gases.
Do halogens have the smallest atomic radius?
The halogens have the smallest atomic radii in their respective periods due to maximum effective nuclear charge. The ionisation enthalpies of halogens are very high. The melting and boiling point of halogens increase with increase in atomic number as we go down the group.
What element has the largest atomic radius?
Atomic radii vary in a predictable way across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. Thus, helium is the smallest element, and francium is the largest.
Which element in group 1 has the greatest atomic radius?
(A) Comparison of Atomic and Ionic Radius of Group 1 (IA, alkali metals) Elements
| Element | Symbol of Atom | Trend |
|---|---|---|
| sodium | Na | ↓ |
| potassium | K | ↓ |
| rubidium | Rb | ↓ |
| cesium | Cs | ↓ largest |
What is the largest atomic radius in Group 18?
The Electron Configurations for Noble Gases
| Atomic # | Atomic radius (pm) | |
|---|---|---|
| Ar | 18 | 71 |
| Kr | 36 | 88 |
| Xe | 54 | 108 |
| Rn | 86 | 120 |
How do you find atomic radius?
The radius of an atom can only be found by measuring the distance between the nuclei of two touching atoms, and then halving that distance. As you can see from the diagrams, the same atom could be found to have a different radius depending on what was around it. The left hand diagram shows bonded atoms.
What has a larger atomic radius Li or K?
K has two shells (n=4 vs n=2) more than Li, so it would be much larger. the electronic structure of atoms: principle quantum number, effective nuclear charge, etc.) C will have the slightly larger radius because it has one less proton and thus, a lower effective nuclear charge.
Why is K bigger than Br?
Since potassium is located at the start of period 3, and bromine at the end of the same period, potassium will have a larger atomic radius than bromine, and thus the largest atomic radius of the four given atoms.
Why does atomic radius increase from right to left?
This is caused by the increase in the number of protons and electrons across a period. One proton has a greater effect than one electron; thus, electrons are pulled towards the nucleus, resulting in a smaller radius. Atomic radius increases from top to bottom within a group. This is caused by electron shielding.
Why does K have a larger atomic radius than na?
As an example, potassium (K) has a larger average atomic radius (220 pm)than sodium (Na) does (180 pm). The potassium atom has an extra electron shell compared to the sodium atom, which means its valence electrons are further from the nucleus, giving potassium a larger atomic radius.
Which has a larger atomic radius S or S2?
(ii) Explain why the radius of the S2- ion is larger than the radius of the S atom. The nuclear charge is the same for both species, but the eight valence electrons in the sulfide ion experience a greater amount of electron-electron repulsion than do the six valence electrons in the neutral sulfur atom.
Does atomic radius increase from left to right?
The atomic radius of atoms generally decreases from left to right across a period. The atomic radius of atoms generally increases from top to bottom within a group.
Which has the largest atomic radius n SB as?
Antimony(Sb) has the largest atomic radius because it has more number of shells as compensation to the other elements..