Classification Of Elements And Periodicity In Properties

- Get the best out of this chapter by practicing the kind of problems asked in various Exams!
Pattern- Trends in the periodic table
Periodic trends are patterns that are present in the periodic table that illustrate the different aspects of an element, including its size and other properties. Questions on periodic trends across groups and periods are asked on electronegativity, ionization energy, electron affinity, atomic radius, melting point, and metallic character. The question type is usually to arrange the given elements in increasing or decreasing order to the trend asked or to select the element that shows the highest or lowest order of the trend.
How to approach
While solving questions related to it, you should know about periodic trends.
To make these things simpler, please go through the important trends given below. Once you know the trends you can easily arrange them in the order asked and find the answer. Also, keep in mind that there are certain exceptions to the general trends. So, do not forget to factor those in while solving questions
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Try to solve these questions to get the idea:
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Pattern- Electronic configuration
Electronic configuration of an element describes how electrons are distributed in the atomic orbitals.
Questions will be based on identifying the correct electronic configuration. Questions are also asked to identify elements having high or low ionization potential based on the electronic configuration.
How to approach:
While solving questions related to it, you should be thorough with electronic configuration of elements.
Also, keep the following points in mind
  • Electron configurations can also predict stability.
  • Atoms with half-filled and fully-filled outer shell configuration are very stable.
  • An atom having a more stable electronic configuration has a lower tendency to lose electrons and consequently has higher ionization energy.
Try to solve these questions to get the idea:
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Pattern- Problems based on isoelectronic species
Questions on this topic will be generally based on finding the isoelectronic species from the given examples. Question can also be asked to find which among the given example is not an isoelectronic species.
How to approach:
First of all, you need to know the term isoelectronic - it refers to atoms, ions, or molecules that have the same number of electrons.
To solve such questions you will have to find out number of electrons present in each of the given examples and then cross-check with the given examples for the same number of electrons.
Now let's practice some problem:
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