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प्रश्न
The number of periods and groups in the periodic table are ______
पर्याय
6, 16
7, 17
8, 18
7, 18
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उत्तर
The number of periods and groups in the periodic table is 7, 18.
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संबंधित प्रश्न
An element X is in group 2 of the periodic table What will be the formula of its chloride?
As element X has mass number 40 and contains 21 neutrons in its atom. To which group of the periodic table does it belong?
An atom has the electron structure of 2, 7.
(a) What is the atomic number of this atom?
(b) To which of the following would it be chemically similar?
7N, 15P, 17Cl, 18Ar
(c) Why would you expect it to be similar?
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.
The elements Li, Na and K, each having one valence electron, are in period 2, 3 and 4 respectively of modern periodic table.
(i) In which group of the periodic table should they be ?
(ii) Which one of them is least reactive ?
(iii) Which one of them has the largest atomic radius ? Give reason in justify your answer in each case.
What was the basis of the earliest attempts made for classification and grouping of elements?
State whether true or false. If false, correct the statement.
Metals can gain electrons.
Match the following
| 1. | Galvanisation | Noble gas elements |
| 2. | Calcination | Coating with Zn |
| 3. | Redox reaction | Silver-tin amalgam |
| 4. | Dental filling | Alumino thermic process |
| 5. | Group 18 elements | Heating in the absence of air |
Identify the bond between H and F in the HF molecules.
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?
