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प्रश्न
Give a reason why elements need to be properly classified.
उत्तर
Reason of classification of elements:
- It makes the study of elements in an organized manner.
- To help and correlate the properties of elements with the fundamental properties of different states of matter.
- To help to define the relationship of one element with others.
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संबंधित प्रश्न
The element X forms a compound X2Y. Suggest an element that Y might be and give reasons for your choice.
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(a) Which two elements will form a covalent compound?
(b) Which two elements will form an ionic compound?
Write the names and symbols of two very reactive metals belonging to group 1 of the periodic table. Explain by drawing electronic structure, how either one of the two metals reacts with a halogen. With which name is the bond formed between these elements known and what is the class of the compound so formed known? State any four physical properties of such compounds.
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(b) To which group of periodic table does X belong?
(c) Name the periodic table in which X is placed.
(d) Which element is placed just before X in the period?
(e) Which element is placed just after X in the period?
Rearrange the columns 2 and 3 so as to match with the column 1.
| Column 1 | Column 2 | Column 3 |
| i. Triad ii. Octave iii. Atomic number iv. Period v. Nucleus vi. Electron |
a. Lightest and negatively charged particle in all the atoms b. Concentrated mass and positive charge c. Average of the first and the third atomic mass d. Properties of the eighth element similar to the first e. Positive charge on the nucleus f. Sequential change in molecular formulae |
1.Mendeleev
2. Thomson
3. Newlands
4. Rutherford
5. Dobereiner
. Moseley
|
How did the early chemists classify elements?
Which one of the following statements is not correct about the trends in the properties of the elements of a period on going from left to right?
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What type of oxide would Eka– aluminium form?
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- Identify the element
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