filter
  • Subject:

    ...

  • Chapter:

    ...

deepika soni
2 years ago | Chemistry | Classification of Elements and Periodicity
Physics Teacher (9354534040)
a year ago
  • Hello Deepika soni

    the electron affinity(Eea) of an atom or molecule is defined as the amount of energy released or spent when an electron is added to a neutral atom or molecule in the gaseous state to form a negative ion.

    thank you.

Khushbu
a year ago | Chemistry | Classification of Elements and Periodicity
  • sir , how to calculate oxidation state?

NEETprep
a year ago
  • Please watch this video

Divyansh kumar Singh
a year ago | Chemistry | Classification of Elements and Periodicity
  • How to conparc rodius in case of isoelectronic species

  • Reference Video
NEETprep
a year ago
  • The size of isoelectronic species depends on nuclear charge. Greater the nuclear change, smaller would be the size.

Shashank Shivam
a year ago | Chemistry | Classification of Elements and Periodicity
  • In group 15,from Sb to Bi size increase but not as much expected,

    Is this because of both d and f contraction or only f contraction?

Mayank Mishra
a year ago
  • Both. SB and Bi have completely filled d and f subshells which have least shielding effects. Thus they do not guard the valence electrons feel the almost whole nuclear charge. This results in the attraction of valence electrons towards nucleus and hence size decreases.

Alisha
a year ago | Chemistry | Classification of Elements and Periodicity
  • one charge less oxygen km krne pr to   ite   suffix lagta h pr sir n   ate suffix lagaya and   per   prefix hata diya   why??

  • Reference Video
Physics Teacher (9354534040)
a year ago
  • This is because of highest oxidation state of Cl in Clo4(-) and Clo3(-) but in Clo4(-) it has max oxygen so differentiate between both the "ate" prefix has been used.

    PS: please watch the video carefully again for better understanding. You will get your answer. 

Alisha
a year ago | Chemistry | Classification of Elements and Periodicity
  • 218+98=316

    sir n glt add kiya and naming bhi glt ho gy h??

  • Reference Video
Physics Teacher (9354534040)
a year ago
  • we are sorry for this mistake. Inconvenience caused is deeply regreted.

    316 is the right answer and hence the name will be (Triunhexium).

Alisha
a year ago | Chemistry | Classification of Elements and Periodicity
  • three B kese ho gya block number lanthanum ka??

    sir n btaya ki d-block elements are placed in subgroup A and lanthanum ka valence electron to 2 h to block nuber 2 hona chahiye

    hence 2A block number hona chahiye lanthanum ka??

    plz clear this doubt

  • Reference Video
Physics Teacher (9354534040)
a year ago
  • hello alisha

    the ground state configuration of lanthanum is an exception of Aufbau rule.

    Request you to watch this video again for the better understanding.

    thank you

Alisha
a year ago | Chemistry | Classification of Elements and Periodicity
  • kyu krenge 0.85 s multiply phle wale questn m to sr n 0.35 s multiply kra tha??

    value chnge kyu krni h reason

  • Reference Video
Physics Teacher (9354534040)
a year ago
  • For ns or np valence electrons

    1. electrons within same group shield 0.35, except the 1s which shield 0.30
    2. electrons within the n-1 group shield 0.85
    3. electrons within the n-2 or lower groups shield 1.00

    this is the rule used to calculate the effective nuclear charge.

Kaushik medhi
a year ago | Chemistry | Classification of Elements and Periodicity
  • Why it's answer is not b question no. 78

Physics Teacher (9354534040)
a year ago
  • Hello Kaushik 

    We are not allowed to answer the question outside from the NCERT and the platform videos. Apert from this please let us know the correct option. So that i can explain you this in a better way.

    thank you.

Alisha
a year ago | Chemistry | Classification of Elements and Periodicity
  • bt sr n to btaya tha ki kisi 1 element ka electron affinity and ionisation enthalpy ki value same hoti h

    to sr yha kyu kh rhe h ki IE not equal to Ea??

  • Reference Video
Physics Teacher (9354534040)
a year ago
  • Hello alisha 

    thanks for informing us. We will fix it as soon as possible and let you know when its done.

    thank you.