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प्रश्न
Explain structure of modern periodic table in short.
उत्तर
- The modern periodic table consists of seven horizontal rows called the periods and eighteen vertical columns called the groups.
- The arrangement of the periods and groups results in the formation of boxes, where each box corresponds to the position of an element.
- Atomic numbers are serially indicated in the upper part of these boxes.
- In addition to these seven rows, lanthanide and actinide series are shown separately at the bottom of the periodic table. The first row is lanthanide series and the second row is actinide series.
- There are 118 boxes in the periodic table including the two series. vi. The entire periodic table is divided into four blocks: s-block, p-block, d-block and f-block.
- s-block: contains group 1 and 2 elements
p-block: contains group 13 to 18 elements
d-block: contains group 3 to 12 elements (transition elements)
f-block: contains lanthanide and actinide series - A zig-zag line is drawn in the p-block of the periodic table. Metals lie on the left side while nonmetals lie on the right side of this line. Metalloids lie along the border of this line.
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संबंधित प्रश्न
How does the metallic character of elements in Modern Periodic Table vary on moving from left to right in a period, and (ii) down a group?Give reason to justify your answer.
How does the tendency of elements to gain electrons change as we move from left to right in a period? State the reason of this change.
Fill in the following blank with suitable word:
Group 18 elements are called ...............
What is meant by a group, in a periodic table?
The atomic numbers of four elements P, Q, R and S are 6, 8, 14 and 16 respectively. Out of these, the element known as metalloid is:
(a) P
(b) Q
(c) R
(d) S
Helium and neon are unreactive gases. What, if anything, do their atoms have in common?
From the standpoint of atomic structure, what determines which element will be the first and which the last in a period the periodic table?
The following diagram shows a part of the periodic table in which the elements are arranged according to their atomic numbers. (The letters given here not the chemical symbols of the elements):
| a 3 |
b 4 |
c 5 |
d 6 |
e 7 |
f 8 |
g 9 |
h 10 |
|
| i 11 |
j 12 |
k 13 |
l 14 |
m 15 |
n 16 |
o 17 |
p 18 |
(i) Which element has a bigger atom, a or f?
(ii) Which element has a higher valency, k or o?
(iii) Which element is more metallic i or k?
(iv) Which element is more non-metallic, d or g?
(v) Select a latter which represents a metal of valency 2.
(vi) Select a letter which represents a non-metal of valency 2.
Define:- Periodic table
Give the group number of following elements present in periodic table
Name the scientist who stated the modern periodic law.
Correct the statement.
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Name the metals in the first twenty elements.
Arrange the elements of second and third periods in increasing order of their atomic size.
Third Period.
Fill in the blank:
The horizontal rows in the periodic table are called _____________.
Write a short note.
Position of isotopes in the Mendeleev’s and the modern periodic table.
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Give the symbol and valency of the following element and radical.
Sodium
Give the symbol and valency of the following element and radical.
Aluminium
What are the periods in a periodic table?
p-block is composed of groups 1 and 2.
Write scientific reason.
There was ambiguity about the correct position of hydrogen in Mendeleev’s periodic table.
Distinguish between:
Group 17 - Group 18
The scientist who propounded the modern periodic law is ______.
Identify gas A in the following experiment.
In the modern periodic table, elements are arranged according to their ______
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Which of the following statements about the Modern Periodic Table is correct:
Which of the following is the outermost shell for elements of period 2?
Which of the following elements does not lose an electron easily?
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.
Choose an element from period 3 of modern periodic table that matches the description given below in instance. Give a reason for your choice.
It has same valency as Lithium.
______ group elements are called alkaline earth metals.
A part of modern periodic table is given below. On its basis, answer the following questions:
| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
Which of the element is a Metalloid?
Explain giving reason why although the nuclear charge in atoms increases in moving from left to right in a period as well as in moving from top to bottom in a group in the Modern periodic table, but the size of the atoms does not vary similarly in both situations.
Name the metalloids in the first twenty elements.
Match the atomic number with the following:
A rare gas.
