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Atomic radius decreasing across a Periodic Table row - does the RPD of an orbital change depending of the element considered?

I have a concern regarding the RPD of an orbital. Does the RPD of an orbital depend on the $Z$ (i.e. on the element under consideration) ? Especially, can the RPD of an orbital "shrink" to ...
niobium's user avatar
  • 267
-1 votes
1 answer
211 views

Ionic radii of cations and anions

My textbook mentions that across a period from left to right, the ionic radius of atoms decreases. I'm a bit puzzled because negative ions in the same period have an extra shell. I get the part about ...
Andrés de Fonollosa's user avatar
1 vote
2 answers
105 views

Does Cu+ have a greater ionic radius than Sr2+?

Although Strontium is in group 2, reducing the number of electrons as it becomes ionized makes it group 18, period 4 in terms of electrons. Therefore, ionized Strontium (Sr2+) is in the same period as ...
Woo Luke's user avatar
3 votes
4 answers
717 views

Comparison of atomic radii of boron and beryllium

Let me write down a couple of facts and this will be easier for you to know the essence of the question. Radius of boron is smaller than beryllium. Ionization energy of boron is smaller than ...
Matt's user avatar
  • 143
0 votes
2 answers
324 views

Why ionic radius increases with negative charge?

Here's my understanding: An ion with a negative charge has gained electrons. Hence the negative charge. With a greater negative charge, there should be more attraction towards the positive charge. As ...
Quin Gardiner Bax's user avatar
2 votes
1 answer
2k views

Why are hydrated lithium ions' radii larger than hydrated sodium ions' radii?

Why are hydrated lithium ions' radii larger than hydrated sodium ions' radii i.e. $r_\ce{Li+(aq)}>r_\ce{Na+(aq)}$? If ionic radii increase down the group i.e. $r_\ce{Li+}<r_\ce{Na+}<r_\ce{K+}$...
user avatar
3 votes
3 answers
7k views

Which atom is the smallest atom?

Is hydrogen or helium the smallest atom? My teacher said that the smallest atom is the helium atom, but I think that the smallest atom is the hydrogen atom. It has a single electron and a single ...
user avatar
5 votes
1 answer
3k views

Why does magnesium have a greater ionization energy than lithium?

I'm a high school student and I'm learning about ionization energy and atomic radius of elements. I want to compare the ionization energy of lithium and magnesium. Here is the information provided in ...
Oshawott's user avatar
  • 291
3 votes
1 answer
798 views

Why is strontium(II) ion bigger than krypton atom?

$\ce{Sr^2+}$ is exactly the same as $\ce{Kr}$, in terms of electrons and orbitals. The only difference between the two, is that $\ce{Sr^2+}$ has a couple of extra protons in the nucleus (and probably ...
peppa's user avatar
  • 39
1 vote
0 answers
310 views

Why is the increase in covalent radius from As to Bi not as big as from N to P?

The following is the radius of Group $15$ elements: $$\begin{array}{c|c} \hline \text{Element} & \text{Covalent Radius }(\pu{pm}) \\ \hline \ce{N} &75 \\ \ce{P} &110 \\ \ce{As} &...
Kaushik's user avatar
  • 236
5 votes
1 answer
1k views

Covalent atomic radii: oxygen vs nitrogen

Many books state that $R_\ce{N} > R_\ce{O}$ which is in accordance with the general trend. However, some books say that $R_\ce{O} > R_\ce{N}$ because of repulsion caused by pairing of electrons. ...
DatBoi's user avatar
  • 264
1 vote
0 answers
302 views

Why doesn't core charge increase down a group? [closed]

Atomic radius increases down a group because the electrons feel a lesser attraction to the positive nucleus (due to shielding from inner shells). Why then, doesn't core charge decrease seeing as core ...
An0n1m1ty's user avatar
  • 151
1 vote
0 answers
1k views

Why is the strontium ion smaller than the potassium ion? [closed]

The ionic radius of the $\ce{Sr^2+}$ ion is $\mathrm{132\,pm}$, while the ionic radius of the $\ce{K^+}$ ion is $\mathrm{152\,pm}$. Why is this the case? I would have thought that since $\ce{K^+}$ has ...
Zander's user avatar
  • 19
6 votes
1 answer
2k views

Why is platinum denser than gold?

The atomic masses of gold and platinum are 196.96657 u and 195.084 u respectively, meaning that (on average) an individual gold atom is heavier than an individual platinum atom. At the same time, the ...
Shubhang Walavalkar's user avatar
2 votes
1 answer
130 views

Shielding effects and atomic size [closed]

The atomic size on going from aluminum to gallium decreases because of poor shielding effect of the $(n-1)d$ electrons, but on going from copper to zinc, the size increases due to the same shielding ...
Aryan goyal's user avatar
1 vote
0 answers
452 views

Relationship between electronegativity and atomic radius [closed]

Would someone please explain in detail the relationship between the two? I understand that atomic radius is related to ionisation energy but I can't see how atomic radius may be related to ...
Clement Maximilian Guinard's user avatar
2 votes
1 answer
2k views

Lanthanoid Contraction

Why is the radius of Europium so unusually high and out of the general trend ? Moreover, at different sources I am getting different values of radii. In some (e.g., Wikipedia) the radii are following ...
Nisarg Upadhyaya's user avatar
3 votes
0 answers
560 views

Why are the Covalent Radii of Ruthenium and Osmium So Similar?

Osmium and Ruthenium have covalent radii 144 and 146 respectively (according to Wikipedia). How are these values so similar when Osmium has 32 more electrons, with another filled p, s, and f orbital ...
Noah Harris's user avatar
1 vote
0 answers
452 views

Mismatch in the trends of atomic size and atomic radius

In the periodic table, the atomic radius decreases as we move from left to right in a period. However, the atomic volume should also decrease as a result of the decrease in atomic radius, as volume is ...
Aniruddha Deb's user avatar
1 vote
2 answers
4k views

Which element has larger atomic radius -- beryllium or xenon?

I say that xenon radius is smaller comparing to beryllium, but my friend says otherwise. What I think is that xenon is down in periodic table comparing to beryllium (3 periods down) and it's far ...
Jason C's user avatar
  • 21
3 votes
2 answers
18k views

Is there regular decrease in atomic radii of 3d series?

The following fragment of the table of atomic radii from CrystalMaker — Elements, Atomic Radii and the Periodic Table shows a regular decrease in the atomic radius of 3d series: Table of Atomic Radii ...
Arishta's user avatar
  • 4,197
9 votes
2 answers
17k views

Why the radius of noble gases is more than the halogens or the previous groups?

Noble gases have larger radii than that of halogens. Sometimes it is greater than the radius of group I elements. Why is it like that? When we talk about radii of noble gases, what type of radius is ...
user136782's user avatar
10 votes
1 answer
2k views

Trend in atomic radius for noble gases

In an exam, we were given the following graph and asked to explain why the slope of the change in r vs. Z changes dramatically at a point along the curve. I understand that the d block causes the ...
Niels Kornerup's user avatar
5 votes
2 answers
16k views

Why is the ionic radius of Al(3+) smaller than that of Li+?

I was examining the ionic radii of some ions from this site for a school assignment. I noticed a weird anomaly in the ionic radius of $\ce{Li+}$ as compared to that of $\ce{Al}^{3+}$. The ionic ...
user avatar
4 votes
2 answers
2k views

Why is there a discrepancy among sources on the atomic radius of some elements?

My book says the atomic radius of gallium is less than that of aluminium, but I found out different atomic sizes on different sites. For example, this says gallium is 136 pm and aluminium is 118 pm, ...
Krishna behera's user avatar
0 votes
1 answer
5k views

Comparing radii in lithium, beryllium, magnesium, aluminium and sodium ions

Apparently the of last four, $\ce{Mg^2+}$ is closest in radius to $\ce{Li+}$. Is this true, and if so, why would a whole larger shell ($\ce{Mg^2+}$) be closer in radius to $\ce{Li+}$ than its ...
user28625's user avatar
  • 161
0 votes
1 answer
5k views

Ionization energy and Electron Affnity

Which of the following statements correctly interprets the relationship between ionization energy, atomic radius Electron affinity when comparing two atoms. The correct choice as per my instructor ...
user22387's user avatar
3 votes
0 answers
374 views

Why do some elements such as polonium not follow the trend of decreasing atomic radius?

Most of the periodic table follows the trend of increasing radius as you move down a family and decreasing radius as you move across a period. Why is this trend not observed for polonium?
jackel's user avatar
  • 31
6 votes
3 answers
38k views

Variation in atomic sizes in the transition elements

From left to right across a period, effective nuclear charge increases in the transition series, just like in the p block, and so atomic size decreases. Here the electrons are being added to the d ...
Anne's user avatar
  • 427
14 votes
2 answers
36k views

Why are the atomic radii of iron, cobalt, nickel, and copper almost the same?

We have to select the set of elements which will have almost the same atomic radii: $\ce{O, S, Se, Te}$ $\ce{Li, Be, B, C}$ $\ce{Fe, Co, Ni, Cu}$ I googled the atomic radii of the third set and ...
Abhishek Mhatre's user avatar
2 votes
1 answer
8k views

Variation in atomic radii of elements in different blocks?

If we look at the values for the atomic radii (look at the table here), we can see that they rapidly decrease across the period initially. Looking at the second period, The graph is pretty steep ...
Gerard's user avatar
  • 3,499
4 votes
2 answers
5k views

Atomic radii of Sc, Ti, Fe, and Co

The atomic radius of Sc is $\pu{162pm}$, Ti is $\pu{147pm}$, $\ce{Fe}$ is $\pu{126pm}$, and that of $\ce{Co}$ is $\pu{125pm}$. The electronic configuration of $\ce{Fe}$ is $\ce{[Ar] 3d^6 4s^2}$, and ...
biogirl's user avatar
  • 1,380