Question 1 :
The eight group of Mendeleev's periodic table is divided into how many subgroups?

Question 4 :
The element placed with cerium, in the table formed by Newlands' was :

Question 5 :
The family of elements having seven electrons in the valence shell is :

Question 6 :
In Mendeleev's periodic table, the elements were arranged in the increasing order of their atomic masses. However, cobalt with atomic mass of 58.93 amu was placed before nickel having an atomic mass of  58.69 amu. Reason for the same is that :

Question 7 :
Which of the given elements A, B, C, D and E with atomic number $2,\,3,\,7,\,10$ and $30$ respectively belong to the same period?

Question 8 :
Which of two elements among the following will display the most similar chemical properties?

Question 9 :
On moving from left to right across a period in the table, the metallic character :<br/>

Question 10 :
In the Periodic Table, how does the metallic character of the elements vary from left to right across a period?

Question 12 :
Assertion: The Newland's law of octaves fail. Reason: The properties of elements beyond atomic weight 40 cannot be explained.

Question 14 :
The name given by Newlands to the arrangement created by him was :

Question 15 :
Which of the following is the correct set of elements to Dobereiner's triads ?

Question 16 :
In modern periodic table, if two elements have the same number of valence electrons, then they belong to the same&#160;:<br/>

Question 17 :
The most significant contribution towards the&#160;development of periodic table was made by:<br/>

Question 18 :
Which one of the following does not increase while moving downthe group of the periodic table?<br>

Question 20 :
The pair of atomic numbers belonging to the same group are:<br/>

Question 21 :
In Newlands' table, which of the following elements was not placed in the same group in which cobalt and nickel were present?

Question 22 :
If X and Y are two elements which belong to same group of Newland's periodic table, how many elements exists between X and Y?

Question 23 :
The number of elements known in Mendeleev's presented periodic table is:<br/>

Question 27 :
Which of the following triads does not follow Dobereiner's law of triads?

Question 28 :
In Newland's classification, elements are arranged in an increasing order of their:

Question 29 :
The&#160;atomic number of&#160;an&#160;element x is 12. The&#160;element left to it and right to it in same period of&#160;periodic table are :

Question 32 :
The element having the least size from the following is :

Question 34 :
All the $s-$ block elements of the periodic table are placed in the groups

Question 35 :
Pentavalence in phosphorus is more stable when compared to that of nitrogen even though they belong to same group is due to :

Question 36 :
The metallic character of elements __________ in a group from top to bottom.

Question 37 :
An element has cubic close packed structure. The distance between adjacent layers is $424.2$ pm. What would be the atomic radius of the element?

Question 38 :
The metal which does not give amphoteric oxide in the solution?

Question 39 :
Which of the following set of elements is writtenin order of their increasing metallic character?

Question 40 :
Assertion: Titanium, Zirconium, and Hafnium belong to the same group. The density of $Zr$ is slightly greater than titanium, But the density of Hafnium is double to that of $Zr$.&#160; Reason: Scandium and Titanium, as well as yttrium and zirconium, have successive atomic numbers. They show a normal trend of transition elements but their atomic numbers are not successive. The 14 elements intermediate between them have 14 electrons filled in $4f$ sub-shell. Due to the lanthanide contraction, there is a decrease in size.