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प्रश्न
Define periods of modern periodic table.
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उत्तर
The horizontal rows are called periods. The table consists of 7 periods, numbered from 1 to 7 from top to bottom.
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संबंधित प्रश्न
Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the Periodic Table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?
Fill in the following blank with suitable word:
Group 18 elements are called ...............
Give two example of group 18 elements.
On which side of the periodic table will you find non-metals?
What is the usual number of valence electrons in the atoms of the last element in a period?
State how the valency of elements varies in a period of the periodic table?
What is the main characteristic of the last elements in the periods of the periodic table? What is the general name of such elements?
In the modern Periodic Table, why does cobalt with higher atomic mass of 58.93 appear before nickel having lower atomic mass of 58.71?
From the standpoint of atomic structure, what determines which element will be the first and which the last in a period the periodic table?
What are the periods in a periodic table? Give two characteristics of each.
The elements A, B, C and D belong to groups 1, 2, 14 and 17 respectively of the periodic table. Which of the following pairs of elements would produce a covalent bond?
(i) A and D
(ii) C and D
(iii) A and B
(iv) B and C
(v) A and C
How many groups and periods does the modern periodic table have?
Name the noble gas with 3 shells.
What is the number of elements in the 1st period?
How does number of (i) valence electrons (ii) valency; vary on moving from left to right in the second period of a periodic table?
Give the symbol and valency of the following element and radical.
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Give the symbol and valency of the following element and radical.
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Give the chemical formula of magnesium nitrate
State what the group number in the Modern Periodic Table signifies. Give a reason why elements in the same group, have similar valency and similar chemical properties.
How were elements arranged in the long form of the periodic table or the Modern Periodic Table?
Compare Modern Periodic Law with Mendeleev's Periodic Law.
Write an Explanation.
Period
In the modern periodic table, the positions of 1 to 20 elements are shown here. Identify the elements A and B. Write their atomic number.
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The longest period of the Modern Periodic Table is period.
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Which of the following elements does not lose an electron easily?
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- Y has 12 protons and 10 electrons
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It has variable valency and is a member of the Oxygen family (group 16).
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Spot the error:
The elements of group 13 are called the carbon family.
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 |
Write the molecular formula of the compound formed by the combination:
E and B
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Answer the following question in relation to the above group of elements:
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