Questions tagged [periodic-trends]
Trends which are observed in the properties of elements as you move along the periodic table in a given direction.
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Effective nuclear charge increases along period despite increasing number of electrons
I learned that when an increasing number of electrons are present in the orbitals, then nuclear force decreases as it needs to hold more electrons.
Given this, why does the effective nuclear charge ...
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Why does chlorine have a higher electron affinity than fluorine?
Since fluorine has its valence electrons in the n=2 energy level, and since chlorine has its valence electrons in the n=3 energy level, one would initially expect that an electron rushing towards ...
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Why does chlorine have a higher electron affinity value than fluorine? [duplicate]
Why does chlorine have a higher electron affinity value than fluorine? Since this periodic property tends from the bottom up (in the group), the logic would be that the fluorine is the element with ...
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Why does the electron affinity increase become more exothermic down group 2 and group 5?
It is generally true that the electron affinity becomes less exothermic down a group, because of the increase in atomic radius.
There is a well-known exception that the electron affinity of Cl is ...
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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 ...
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Why is ionization energy of indium less than gallium?
In group 13 we observe an irregular trend in ionization energy: B > Tl > Ga > Al > In.
Gallium has a filled 3d subshell, but indium has a filled 4d and 3d subshell. Thus it should have more poor ...
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Why does the 1st ionisation energy decrease from the 9th period to the 10th period
I’m currently looking at the ionisation energy chart within my chemistry textbook and while I know that there are not really meaningful periodic trends within transition metals, generally the ...
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Are Fajans rules relevant to melting and boiling points of alkali metal hydrides?
Among LiH, NaH, KH, RbH, CsH the one with the highest melting point is LiH, and it keeps on decreasing till CsH. The reason for this in my textbook is that the size of cations keeps on increasing down ...
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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 ...
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I was told that Lithium and group 2 bicarbonates does not decompose on heating.Group 1 bicarbonates does decompose except lithium
But in some sources it was explained that stability of group 1 bicarbonates increases down the group.If it is true then how does lithium bicarbonate does not decompose ?.Can anyone please tell me ...
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Upon what does the half life of a nuclide depend on? [duplicate]
Nuclide half-lives seem to be apparently random, except for the fact that heavier elements are typically radioactive and lighter ones stable. Is there any factor that can predict the half life of a ...
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Second ionization energies of copper(Cu) and silver(Ag)
The ionization energies of copper and silver are
First ionization energy: Cu-745.5 kJ/mol Ag-731.0 kJ/mol
Second ionization energy: Cu-1958 kJ/mol Ag-2073 kJ/mol
Now, looking at the ionization ...
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Why aren't other elements with valence 6s electrons liquid like mercury?
I found out that mercury's 6s electrons undergo relativistic effects that make their pull to the nucleus greater, which makes it so that they can't bond with other atoms of mercury to form a solid. ...
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Abnormal ionisation energy trend: Group 13 and 14
I was going through some ionisation energy data, where I came across the following:
Ionisation energy order for Group 13 and 14:
B > Al ≈ Ga > In < Tl
C > Si > Ge > Sn < Pb
What could be the ...
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Why is the boiling point of heavy water higher than normal water?
In class, we learned that London forces become stronger as relative molecular mass increases. Not just in organic chemistry but in things like the halogens.
However, as I understand, the London forces ...
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