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प्रश्न
Differentiate between Normal elements and Transition elements.
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
Elements in the same group show the same valency. Give scientific reason.
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.
Study the following table in which positions of six elements A, B, C, D, E and F are shown as they are in the modern periodic table:
|
Group→
Period↓ |
1
|
2
|
3-12
|
13
|
14
|
15
|
16
|
17
|
18
|
| 2 | A | B | C | ||||||
| 3 | D | E | F |
On the basis of the above table, answer the following questions:-
(i) Name the element which forms only covalent compounds.
(ii) Name the element which is a metal with valency three.
(iii) Name the element which is a non-metal with valency three.
(iv) Out of D and E, which is bigger in size and why?
(v) Write the common name for the family to which the elements C and F belong.
Two elements ‘A’ and ‘B’ belong to the 3rd period of Modern periodic table and are in group 2 and 13, respectively. Compare their following characteristics in tabular form:-
(a) Number of electrons in their atoms
(b) Size of their atoms
(c) Their tendencies to lose electrons
(d) The formula of their oxides
(e) Their metallic character
(f) The formula of their chlorides
How many groups and periods are there in the modern periodic table?
What is meant by 'group' in the modern periodic table? How do the following change on moving from top to bottom in a group?
(i) Number of valence electrons
(ii) Number of occupied shells
(iii) Size of atoms
(iv) Metallic character of element
(v) Effective nuclear charge experienced by valence electrons
Consider two elements 'X' (Atomic number 17) and 'Y' (Atomic number 20)
(i) Write the positions of these elements in the modern periodic table giving justification.
(ii) Write the formula of the compound formed by the combination of 'X' and 'Y'.
(iii) Draw the electron-dot structure of the compound formed and state the nature of the bond formed between the two elements ?
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?
Choose the most appropriate answer of the following:
Which of the following would weigh the least?
(A) 2-gram atoms of Nitrogen.
(B) 1mole of Silver
(C) 22.4 liters of oxygen gas at 1 atmospheric pressure and 273K
(D) 6.02 x 1023 atoms of carbon.
[Atomic masses: Ag=108, N=14, O=16, C=12]
How do electronic configurations of elements change in second period of periodic table with increase in atomic numbers?
Rewrite the following statement after correction, if necessary:
The metallic character of elements in a period increases gradually on moving from left to right.
How do atomic structures (electron arrangements) change in a period with increase in atomic numbers from left to right?
An element which is an essential constituent of all organic compounds belongs to following group of modern periodic table:
(a) group 4
(b) group 14
(c) group 15
(d) group 16
What do you understand by orbits?
Name two elements you would expect to show chemical reactions similar to calcium. What is the basis of your choice?
An element X belong to 4th period and 17th group, state.
name of the element.
How does the number of:
valence electrons and
State the number of elements in periods 1, Periods 2, and Period 3 of the periodic table. Name them.
An element 'M' has atomic number 12.
(a) Write its electronic configuration.
(b) State the group to which 'M' belongs.
(c) Is 'M' a metal or a non-metal.
(d) Write the formula of its chloride.
Calculate the valency of element X whose atomic number is 9.
On the basis of electronic configuration, how will you identify the first and the last element of a period?
K, Pb, Ca, Zn (In the increasing order of the reactivity)
State whether the following statement is true or false
On moving horizontally across a period, number of valence electrons increases from one to eight.
How could the atomic radius of a noble gas be compared with the other elements in a period?
An element Z has atomic number 16. Answer the following
(a) State the period and group to which Z belongs
(b) Is Z a metal or a non-metal?
(c) State the formula between Z and hydrogen.
(d) what kind of a compund is this?
Choose the most appropriate answer from the following list of oxides which fit the description.
A basic oxide.
Choose the most appropriate answer from the following list of oxides which fit the description.
An amphoteric oxide: Al2O3 (shows both acidic and basic properties)
Choose the word or phrase from the bracket which correctly complete each of the following statement:
Metals are good ................. (oxidising agents/reducing agents) because they are electron ............. (acceptors/donors).
The elements of one short period of the periodic table are given below in order from left to right:
| Li | Be | B | C | O | F | Ne |
One element of this period is missing. Which is the missing element and where should it be placed?
The elements of one short period of the periodic table are given below in order from left to right:
| Li | Be | B | C | O | F | Ne |
Which one of the above elements belongs to the halogen series?
(a) Fill in the blanks and rewrite the completed statements:
(i) ________ group in the periodic table contains elements that are all gases at room temperature.
(ii) Very fine particles mainly scatter ______ light.
The electronic configuration of an element is 2, 8, 4. State it:
group and period in the Modern Periodic Table.
Based on the group valency of element write the molecular formula of the following compound giving justification:
Halide of the elements of group thirteen
The position of certain elements in the Modern Periodic Table is shown below:
Using the above table answer the following questions giving reasons in each case :
(i) Which element will form only covalent compounds?
(ii) Which element is a non-metal with valency 2?
(iii) Which element is a metal with valency 2?
(iv) Out of H, C, and F which has the largest atomic size?
(v) To which family does H, C, and F belong?
State the property trends in general of elements on moving down in a group of the periodic table.
Name or state following with reference to the element of the first three periods of the periodic table.
The non-metallic element present in period 3 other than sulphur and chlorine.
Name or state following with reference to the element of the first three periods of the periodic table.
A non-metal in period 2 having electronic configuration 2, 6.
Name or state following with reference to the element of the first three periods of the periodic table.
A metal in period 3 having valency 3.
Electron Affinity is maximum in ______.
