Advertisements
Advertisements
प्रश्न
What is the need for classification of elements?
Advertisements
उत्तर
It is impossible for a chemist to study all the elements and their compounds. Hence, classification is a must.
Following are the reasons for the classification of elements:
- To study elements better
- To correlate the properties of the elements with some fundamental properties which are characteristic of all the elements
- To reveal relationships between elements
APPEARS IN
संबंधित प्रश्न
An element X is in group 2 of the periodic table what will be the formula of its oxide?
The following diagram shows a part of the periodic table containing first three periods in which five elements have been represented by the letters a, b, c, d and e (which are not their chemical symbols):
-
1 18 a 2 13 14 15 16 17 b c d e
(i) Select the letter which represents an alkali metal.
(ii) Select the letter which represents a nobles gas.
(iii) Select the letter which represents a halogen.
(iv) What type of bond is formed between a and e?
(v) What type of bond is formed between d and e?
The non-metal A is an important constituent of our food and most of the fuels around us. A forms two oxides B and C. The oxide B is poisonous whereas oxide C causes global warming.
(a) Identify A, B and C.
(b) To which group of periodic table does A belong?
(c) Name another element which is placed in the same group as A.
Choose the correct option and rewrite the statement.
The number of electrons in the outermost shell of alkali metals is _______.
(a) How is possible valency of an element determined from the electronic configuration of its atom ?
(b) Determine the valency of an element X whose atomic number is 15.
What was the basis of the earliest attempts made for classification and grouping of elements?
Why was this basis of classification discarded for future classification of elements?
In which group are inert elements placed?
Complete the following triads by inserting the missing elements.
Li, ______, K
How are elements grouped into various families in the periodic table?
