Periodic Classification Of Elements - Class 10 Chemistry - Extra Questions

According to Newlands' assumption, what is the total number of elements in nature?

How and why does the atomic size vary as you go:
(i) from left to right along a period?
(ii) down a group?

State Newland's Law of Octaves. Write the name of the element having similar properties to the following:
(a) Nitrogen
(b) Lithium

S, Se, Te are the elements of a triad. If the atomic weight of Sulphur is 32 and Tellurium is 127.5, the atomic mass of Selenium is ________.

Write down five major differences between Mendeleev's periodic table and Modern periodic table.

Which will be the third element among the given elements to complete the given Doberiener triad?

(Atomic mass of $$\text {Be= 9, Na= 23, Mg= 24, Si= 28, Cl= 35, Ca= 40} $$)
$$\text {Na, __ , Cl}$$

Which will be the third element among the given elements to complete the given Doberiener triad?
(Atomic mass of Be 9; Na 23; Mg 24; Si 28; Cl 35; Ca 40)
Be, ___, Ca

The law used by Newland to arrange elements is known as ___________.

State Newland's law of octaves.

Dobereiner classified elements into groups based on their properties. The number of elements in each group is _______.

The arrangement of elements in a group of three is known as ___________.

Arrange the following as per the instruction given in the bracket:

$$He, Ar, Ne$$ (Increasing order of the number of electron shells).

What are the limitations of Mendeleev's periodic table?

Explain Newlands law of Octaves. Why was the law discarded?

The atomic numbers of five elements $$A, B, C, D$$ and $$E$$ are $$6, 8, 3, 7$$ and $$9$$ respectively.
Which is the element having least metallic character among these elements? Why?

What is valency? Write valency of hydrogen.

Name the scientist who presented 'Law of octave'. 

Can the following groups of elements be classified as Dobereiner's triad:

(a) Na, Si, Cl

(b) Be, Mg, Ca

Justify the answer in each case.

[Atomic mass(in u) of $$Be-9; Na-23; Mg-24; Si-28; Cl-35.5; Ca-40$$]

What were the limitations of Newland's law of octaves?

State one example of a Dobereiner's traid, showing in it that the atomic mass of middle element is half-way between those of the other two.

Among elements with atomic numbers 11 and 14, which has a bigger atomic size?

Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies. 

Can the following groups of elements be classified as Dobereiner's triad?
(a) Na, Si, Cl
(b) Be, Mg, Ca
Atomic mass of Be 9; Na 23; Mg 24; Si 28; Cl 35; CaExplain by giving reason. 

The three elements A, B and C with similar properties have atomic masses X, Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called as? Give one example of such a set of elements. 

An element is placed in 2nd Group and 3rd Period of the Periodic Table, burns in presence of oxygen to form a basic oxide. 
(a) Identify the element
(b) Write the electronic configuration
(c) Write the balanced equation when it burns in the presence of air
(d) Write a balanced equation when this oxide is dissolved in water  
(e) Draw the electron dot structure for the formation of this oxide 

Explain the following :
Group $$ 17 $$ elements are strong non-metals, while group $$ 1 $$ elements are strong metals.

The position of elements $$A,B,C,D$$ and $$E$$ in the periodic table are shown below: 
Group $$1$$Group $$2$$Group $$17$$Group $$18$$

Which is larger in size B or C?

Write the drawbacks in Mendeleev's periodic table that led to its modificaiton.

Why did Mendeleev's leave some gaps in his periodic table of elements? Explain your answer with an example.

Write the name and symbol of the element from the description.
The atom having the smallest size.

Fill in the blank
Moving left to right in the second period, number of valence electrons...............

The electronic configuration of an element $$T$$ is $$( 2 , 8 , 8 , 1 )$$.
Is it a metal or a non-metal? 

What is the location of metals and non-metals in the Modern Periodic Table?

How many triads could Dobereiner identify from the existing elements then ?

Which element in a period has the highest atomic size ?

Fill in the blanks:
Law of triads was given by ............

Fill in the blanks:
........... was introduced by Newlands.

The figure of an incomplete periodic table is given. Which element (named A, B, C, D, E, F, G, H) has the highest atomic radius? Which one has the least?

$$\displaystyle 2 \times 10^8 $$ atoms of carbon are arranged side by side. Calculate the radius of the carbon atom if the length of this arrangement is $$2.4 \ cm$$. 

Considering the element $$B, Al, Mg$$ and $$K$$, write the correct order of their metallic character.

Class 10 Chemistry Extra Questions