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प्रश्न
Write a short note.
Structure of the modern periodic table.
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उत्तर
Structure of the modern periodic table:
Periodic Table: It is the table of chemical elements arranged in order of atomic number such that elements with similar atomic structure appear in the vertical columns. The Modern periodic law states that The chemical and physical properties of elements are a periodic function of their atomic numbers. The modern periodic table is based on modern periodic law.
Groups: There are 18 vertical columns in the periodic table. Each column is called a group. All elements in a group have similar chemical and physical properties because they have the same number of valence electrons.
Periods: In periodic table elements are arranged in a series of rows. Elements of the same period have the same number of electron shells.
Blocks: The table is divided into four blocks: s-block, p-block, d-block, and f-block, based on the type of orbital being filled. s- and p-blocks are called representative elements, d-block are transition metals, and f-block are inner transition elements (lanthanides and actinides).
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संबंधित प्रश्न
Compare and contrast the arrangement of elements in Mendeleev’s periodic Table and the Modern Periodic Table.
What is periodicity in properties of elements with reference to the Modern Periodic Table?
What is meant by a group, in a periodic table?
Give two example of group 18 elements.
What is the name of those elements which divide metals and non-metals in the periodic table?
The three elements having chemical symbols of Si, B and Ge are:
(a) all metals
(b) all non-metals
(c) all metalloids
(d) Si is metalloid, B is metal and Ge is non-metal
The modern periodic table was prepared by ______.
The atomic particle whose number in the atoms of an element always remains the same and which forms the real basis for the modern classification of elements is:
(a) electron
(b) proton
(c) neutron
(d) meson
Give alongside is a part of the periodic table :
As we move horizontally from left to right:
| Li | Be | B | C | N | O | F | |
| Na | Mg | Al | Si | P | S | Cl |
(i) What happens to the metallic character of the elements?
(ii) What happens to the atomic size?
(b) What is the number of elements is 3rd period, the modern periodic table?
What are the groups in a periodic table? Give two characteristics of each.
How many groups and periods does the modern periodic table have?
Correct the statement.
Copper and zinc are representative elements.
Answer the following in respect of element `31/15 P`
Give its electronic configuration
Fill in the blank:
The horizontal rows in the periodic table are called _____________.
What is the number of elements in the 3rd period, of the modern periodic table?
Two elements P and Q belong to the same period of the modern periodic table and are in group 1 and group 2, respectively. Compare the following characteristics in the tabular form.
- Number of electrons in their atoms
- Their tendency to lose electrons
- Their metallic characters
- Formation of their oxides
- Formulae of their chlorides
In the Modern Periodic Table – atoms of all elements are arranged according to their increasing order of – atomic numbers. An atom of nitrogen has seven protons and seven electrons. State what would be its atomic number.
Give the symbol and valency of the following element and radical.
Hydroxide
Give the symbol and valency of the following element and radical.
Carbonate
Give the chemical formula of sodium hydroxide
Fill in the blank:
The element lithium in the Modern Periodic Table with valency 1+ belongs to the group ______.
State the number of elements in Period 1 of the Periodic Table.
State any five features of modern periodic table.
Which of these belong to the same period?
| Element | A | B | C |
| Atomic number | 2 | 10 | 5 |
The element which has the least tendency to lose electrons is ______
On moving from left to right in a period in the periodic table, the size of the atom ______
“Hydrogen occupies a unique position in Modern Periodic Table”. Justify the statement.
Arrange the following elements in the increasing order of their metallic character
| Mg, | Ca, | K, | Ge, | Ga |
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 a similar structure to diamond.
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.
An element belonging to 3d series of modern periodic table has spin magnetic moment = 5.92 B.M. in +3 oxidation state. The atomic number of elements are ______.
Name the metalloids in the first twenty elements.
Name the non-metals in the first twenty elements.
What is the general name of the last elements of the Periodic Table?
An element has 2 electrons in its N shell.
Is it a metal or a non-metal?
Answer the following in respect of element \[\ce{_16^32S}\].
Give its formula with hydrogen.
