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Priyanshu answered 1 year(s) , 10 month(s) ago

write the advantages and disadvantages of mendeleev's periodic table and modern periodic table with examples.

Advantage of Mendeleev Periodic Table :-
1.He left blank  Places which help scientist to discover new element
2.When Noble gasses was discovered Hel could add  it to periodic table without any m...

Asked by Ayushman

Feb 26

  • 8 Answers
Syeda answered 1 year(s) ago

Difference between Mendeleev's periodic table and modern periodic table


Mendeleev's periodic table Modern periodic table Mendeleev's periodic table is based on atomic mass...

Asked by Anuj

Mar 1

  • 3 Answers
Swathi answered 4 year(s) , 6 month(s) ago

Electronic configuration of lanthanoids and actinoids

Generally lanthanides and actinides have electron configurations that follow the Aufbau rule. There are some exception, in a few of the lanthanide and actinide elements.

The electronic configuration


Asked by Dilip

Dec 11

  • 1 Answer
  • 0 Like
Swathi answered 4 year(s) , 5 month(s) ago

What are Dobereiner’s triads?

According to Dobereiner, all elements occurred in groups of three, when arranged in increasing order of atomic masses. He referred to these groups as triads. In a traid the elements had similar chemical prop


Asked by Ketan

Dec 29

  • 1 Answer
Gaurav answered 5 year(s) , 3 month(s) ago

What are the limitations of modern periodic table

Limitations of modern periodic table:
i.              Uncertainty regarding the position of hydrogen whether it should be placed in IA group or VIIA group.
ii.             N...

Asked by Rohit

Jan 24

  • 3 Answers
  • 0 Like
Adhithyan answered 4 year(s) , 3 month(s) ago

Name the compound responsible for depletion of ozone

CFC(Chloro Fluro Carbon) are responsible for depletion of ozone layer.These are found in Ac,sprays and other electric appliances such as Refridgerator

Asked by Rohit

Feb 13

  • 7 Answers
  • 1 Like
Premwati commented 4 year(s) , 3 month(s) ago

Why could no fixed position be given to hydrogen in Mandeleev's periodic table?

It is so because hydrogen has 1 valence electron in its outermost shell.so according to modern periodic table, hydrogen can be arranged in halogen family i.e. group no. 17 but hydrogen does not possess the prop...

Asked by Premwati

Feb 12

  • 2 Answers
  • 0 Like
Swathi answered 4 year(s) , 5 month(s) ago

What are the disadvantages of modern periodic table?

The disadvantages of modern periodic table are

  • Position of hydrogen is not satisfactory,  it can be placed either in group I or 17 group of the first period.

  • It fails


Asked by Gautam

Dec 27

  • 1 Answer
Swathi answered 4 year(s) , 3 month(s) ago

How does the electronic configuration of an atom relate to its position in the modern periodic table?

To know its position in periodic table first we should know the electronic configuration of the element.
For example Oxygen.
Atomic number of Oxygen is 16
Electronic configuration of oxygen


Asked by Usman m u

Mar 9

  • 1 Answer
  • 0 Like
Gaurav answered 5 year(s) , 3 month(s) ago

Uses of inert gases

Uses of Inert Gases:
1. Helium- inflates balloons, as a inert gas shield for welding, protectivegas in growing silicons, helps NASA shuttles get into space.
2. Neon- used for signs, and electron...

Asked by Harikrishnan

Feb 16

  • 4 Answers
Siddharth commented 3 year(s) , 9 month(s) ago

State one reason for placing Mg and Ca in the same group of the periodic table.

Let's see the Electronic configuration of  Mg and Ca
Element   Atomic number        K      L       M       N
Mg                   12                            


Asked by Allie

Feb 6

  • 1 Answer
  • 1 Like
Gaurav answered 5 year(s) , 3 month(s) ago

is there a place for isotopes in modern periodic table , if there ,where are isotopes placed in modern periodic table

Isotopes are nothing but elements with different atomic mass. Modern periodic table doesnt bother abt atomic mass. It focusses only on atomic no.So isotopes dont have any position in the mode...

Asked by Navaneeth

Feb 21

  • 3 Answers
  • 0 Like
Gaurav commented 5 year(s) , 3 month(s) ago

State modern periodic law of classification of elements

Modern peiodic law states that elements are periodic functions of atomic numbers

Asked by Anushree

Feb 24

  • 3 Answers
  • 0 Like
Gaurav answered 5 year(s) , 3 month(s) ago

what is meant by periodicity of properties of elements why are the properties of elements placed in the same group of periodic table

The occurrence (or arrangement) of the elements with similar properties after certain regular interval when they are arranged in increasing order of atomic number is called periodicity. The periodic repetition...

Asked by Jayashree

Mar 5

  • 1 Answer
  • 0 Like
Satyanarayana answered 5 year(s) , 1 month(s) ago

Write the features of Mendeleev’s classification of elements. Give its merits and demerits

   Ans: According to Mendeleev’s Periodic Law  “The Physical and Chemical Properties of the elements are the periodic functions of their atomic weights.”
Mendeleev classi...

Asked by San

Apr 25

  • 1 Answer
  • 0 Like
Swathi answered 4 year(s) , 1 month(s) ago

The first ionization potential of Na, Mg, Al, Si are in the order of

Answer is 1.
Mg has greater ionization energy than aluminium because Mg has stable electronic configuration with completely filled 3s orbital whereas in Al the 3p orbitals are incompletely filled. Moreov...

Asked by P murali

May 1

  • 1 Answer
  • 0 Like
Satyanarayana answered 5 year(s) , 1 month(s) ago

did dobereiner triads also exist in the coloms of newlands octaves.compare and find out.

Dobereiner’s law states that the atomic weight of the middle element in a triad will be equal to the arithmetic mean of atomic weights of other two elements.
Dobereiner’s triads Li Ca Cl Na Sr Br...

Asked by Io

Apr 24

  • 1 Answer
  • 1 Like
Swathi answered 4 year(s) , 2 month(s) ago

State Mendeleev’s Periodic law?

Mendeleev’s periodic law states that "the physical and chemical properties of all elements are the periodic function of their atomic masses".

Asked by Apurbo

Mar 21

  • 1 Answer
  • 1 Like
Swathi answered 4 year(s) , 3 month(s) ago

Helium has atomic number 2 but not placed under group 2 why?

Helium is placed in group 18.  18th group elements are called noble gases due to their completely filled electronic configuration (Octet configuration). But group 2 elements have incompletely fill


Asked by Aditya

Feb 19

  • 1 Answer
  • 0 Like
Swathi answered 4 year(s) , 3 month(s) ago

How could the modern periodic table removes the anomalies of Mendaleev's periodic table?

The long form of periodic table is based on atomic number, which is the more fundamental property. The position of an element in this periodic table is linked to its electronic configuration.


Asked by Aditya D

Feb 14

  • 2 Answers
  • 0 Like
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