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प्रश्न
Differentiate between Normal elements and Transition elements.
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उत्तर
| Normal Elements | Transition Elements |
| Elements belonging to groups 1 and 2, and 13 to 17 are called normal elements. | Elements belonging to groups 3 to 12 are called transition elements. |
| In these elements, all the inner shells are completely filled except the outermost shells. |
In these elements, the outermost shell and next to the outermost shell (penultimate shell) are incomplete. |
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संबंधित प्रश्न
Write the electronic configuration of K and Ne.
Taking the example of an element of atomic number 16, explain how the electronic configuration of the atom of an element relates to its position in the modern periodic table and how valency of an element is calculated on the basis of its atomic number.
An element 'X' has mass number 35 and number of neutrons 18. Write atomic number and electronic configuration of 'X'. Also write group number, period number and valency of 'X'.
An element 'M' with electronic configuration (2, 8, 2) combines separately with (NO3)–, (SO4)2– and (PO4)3– radicals. Write the formula of the three compounds so formed. To which group and period of the Modern Periodic Table does the element 'M' belong? Will 'M' form covalent or ionic compounds? Give reason to justify your answer.
List any two properties of the elements belonging to the first group of the modern periodic table.
The electrons in the atoms of four elements A, B, C and D are distributed in three shells having 1, 3, 5 and 7 electrons in the outermost shell respectively. State the period in which these elements can be placed in the modern periodic table. Write the electronic configuration of the atoms of A and D and the molecular formula of the compound formed when A and D combine.
Write the atomic numbers of two elements 'X' and 'Y' having electronic configuration 2, 8, 2 and 2, 8, 6 respectively.
Name the element that has two shells, both of which are completely filled with electrons.
Which element has a total of three shells, with four electrons in its valence shell?
Use the letters only written in the Periodic Table given below to answer the questions that Follow :
1) State the number of valence electrons in atom J.
2) Which element shown forms ions with a single negative charge?
3)Which metallic element is more reactive than R?
4) Which element has its electrons arranged in four shells?
How does the valency of elements change of moving from left to right in the third period of the periodic table?
State one reason for keeping fluorine and chlorine in the same of the periodic table.
In which part of a group would you separately expect the elements to have the greatest metallic character
In which part of a group would you separately expect the elements to have the largest atomic size?
The electronic configuration of the atom of an element X is 2, 8, 4. In modern periodic table, the element X is places in :
(a) 2nd group
(b) 4th group
(c) 14th group
(d) 8th group
The atomic number of an element is 20. In modern periodic table, this element is placed:
(a) 2nd period
(b) 4th period
(c) 3rd period
(d) 1st period
Where would you locate the element with electronic configuration 2, 8 in the modern periodic table?
Which of the following is the valence shell for the elements of second period of the modern periodic table?
(a) M shell
(b) K shell
(c) L shell
(d) N shell
The element which has the maximum number of valence electrons is:
(a) Na
(b) P
(c) Si
(d) A
The correct increasing order of the atomic radii of the elements oxygen, fluorine and nitrogen is:
(a) O, F, N
(b) N, F, O
(c) O, N, F
(d) F, O, N
Correct the statements.
Elements in the same periods have equal valency.
What do you understand by orbits?
Fill in the blank:
on moving from right to left in the second period, the number of valence electrons……….
An element X belong to 3rd periods and group II of the periodic table state:
the number of valence electrons,
What is the common feature of the electronic configuration of the elements at the end of period 2, and period 3?
F, Cl and Br are the elements each having seven valence electrons. Which of these (i) has the largest atomic radius, (ii) is most reactive? Justify your answer stating reason for each.
Atomic number of metal ‚A‛ is 11, while atomic number of metal ‚B‛ is 20. Which of them will be more reactive? Write the chemical reaction of dilute HCl with metal ‚A‛.
Study the extract of the Periodic Table given below and answer the questions that follow. Give the alphabet corresponding to the element in question. DO NOT repeat an element. 
Which is an inert gas?
What is meant by periodicity of elements?
Fill in the blank
There are ______ groups and ______ periods in the modern form of periodic table.
State whether the following statement is true or false
Similar electronic configuration is repeated after intervals of 2, 8, 8, 18 and 32.
Select the correct answer
Identify the metalloid
Parts (i) to (v) refer to changes in the properties of elements on moving from left to right across a period of the periodic table. For each property, choose the letter corresponding to the correct answer from the choices (a), (b), (c) and (d).
(i) The non metallic character of the elements:
(a) Decreases
(b) Increases
(c) Remains the same
(d) Depends on the period
(ii) The electro negativity
(a) Depends on the number of valence electrons
(b) Remains the same
(c) Decreases
(d) Increases
(iii) The ionization potential
(a) Goes up and down
(b) Decreases
(c) Increases
(d) Remains the same
(iv) The atomic size
(a) Decreases
(b) Increases
(c) Remains the same
(d) Sometimes increases and sometimes decreases
(v) The electron affinity of the elements in groups 1 to 7:
(a) Goes up and down
(b) Decreases and then increases
(c) Increases
(d) decreases
Choose the most appropriate answer from the following list of oxides which fit the description.
An amphoteric oxide.
An element belongs to the third period and Group IIIA (13) of the periodic table. State: the number of valence electrons,
Moving left to right in the second period, the number of valence electrons _____.
Write the electronic configuration of two elements A and B whose atomic numbers are 20 and 17 respectively. Write the molecular formula of the compound formed when element A reacts with element B. State whether this compound is acidic, basic or neutral. Give a reason to justify your answer.
Name or state following with reference to the element of the first three periods of the periodic table.
The formula of the hydroxide of the element having electronic configuration 2, 8, 2.
Give a reason for the following:
A transition from metallic to non-metallic elements is seen on moving from left to right in a period of the periodic table.
