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प्रश्न
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
|
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उत्तर
|
Column I
|
Column II
|
Column III
|
| i. Triad | c. Average of the first and the third atomic mass | 5. Dobereiner |
| ii. Octave | d. Properties of the eight-element similar to the first. | 3. Newlands |
| iii. Atomic Number | e. Positive charge on the nucleus. | 6. Moseley |
| iv. Period | f. Sequential change in molecular formulae | 1. Mendeleev |
| v. Nucleus | b. Concentrated mass and positive charge | 4. Rutherford |
| vi. Electron | a. Lightest and negatively charged particle in all the atoms | 2. Thomson |
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संबंधित प्रश्न
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(ii) Give the formula of the compound formed.
Atoms of eight elements A, B, C, D, E, F, G and H have the same number of electron shells but different number of electrons in their outermost shells. It was found that elements A and G combine to form an ionic compound. This ionic compound is added in a small amount to almost all vegetables and dishes during cooking. Oxides of elements A and B are basis in nature while those of elements E and F acidic. The oxide of element D is, however, almost neutral. Based on the above information, answer the following questions:
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(c) Name another element which is placed in the same group as A.
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Across:
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Down:
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(5) The first element of second Period
(6) An element which is used in making fluorescent bulbs and is second member of Group 18 in the Modern Periodic Table
(7) A radioactive element which is the last member of halogen family.
(8) Metal which is an important constituent of steel and forms rust when exposed to moist air.
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