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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Why middle elements of transition series show more number of oxidation states [duplicate]
Why do the elements in the middle of the transition series show more number of common oxidation states than others?
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Why does the rate of change of atomic radius in the second period change so drastically?
I was reading in my textbook Chemistry Part I, Textbook for Class XI
by NCERT, ed. January 2021 that:
The atomic size generally decreases a period across as illustrated in Fig. 3.4 (a) for the ...
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Reason for exceptions in I.E. trend in group 13
In general, we would expect IE to decrease down a group. This is because atomic radius increases $\implies$ valence electrons are further from nucleus $\implies$ less effective nuclear attraction on ...
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Trends in atomic radii across a period
I am a 12th grader. Recently, while revising the Periodic Table, I came across the statement:
As the effective nuclear charge increases across a period, the atomic radius of the elements decreases on ...
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Why ionization energy of Thallium is higher than that of Indium?
I just normally calculated the effective nuclear charge (Zeff) for thallium and Indium from Slater's law, and I found it same for both! That is 5.(If you want calculation for answering or correcting ...
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Why is effective nuclear charge said to be decreased down the group, but the Zeff calculated is increased down the groups instead?
Some textbook write that effective nuclear charge is constant when gping down the group,while some write that the effective nuclear charge decrease down the group
So which statement is true? I try to ...
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Confusion regarding 1st and 2nd electron gain enthalpy
$\ce{O}$ has the 1st electron gain enthalpy $\pu{-141 kJ mol-1}$. $-ve$ value implies that energy is released when electron is added to an isolated atom. This also means that if $\pu{141 kJ}$ energy ...
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Reason of being 2nd ionization energy
Why is the second ionization energy always greater than the first? By shielding effect, it shouldn't have been true. Let's take $\ce{Mg}$ and $\ce{Mg^+}$ for example. Effective nuclear charge(ENC) for ...
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Extent of Melting of Bonds or Intermolecular Forces
I'm currently having a revisit on the subject of periodicity of the periodic table, and I came across an issue that is kind of bugging me.
If we take a look at the melting and boiling point trends of ...
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Can halogens show -3 or -5 or -7 oxidation state. Why? [closed]
I mean can we think it like if the electrons get excited into the d orbitals and because there are now more than one unpaired electron, why does it only loose them and why don't they accept more than ...
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Doubt regarding trends in modern periodic table [closed]
We know that atomic radius decreases along a period and increases along a group. (Same goes for metallic character)
But if we take 2 elements A & B(A is at somewhere in the top and left in ...
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Why are certain gases with higher molar masses less dense than the ones that have a lower one?
Neon, despite having a larger molar mass than nitrogen, oxygen and fluorine, is less dense than all of them. This also goes that fluorine (again) and chlorine are both denser than argon, even though ...
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Why is reaction of Li less vigorous than that of Na although the former has a more negative SRP value?
My textbooks says:
It may be noted that although lithium has most negative E0 value (Table 10.1), its reaction with water is less vigorous than that of sodium which has the least negative E0 value ...
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Why an atom is more stable when only sublevels s and p are full?
Supposedly when explaining electronegativity and stability of an element, they tell you that it is more stable if the last level is full. That works up to the third period, but after transition ...
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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. $r_\ce{Li+}<r_\ce{Na+}<r_\ce{K+}$...
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