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प्रश्न
Select the correct answer from the options given below.
It is a period having elements from atomic no. 11 to 18.
पर्याय
period – 1
period – 2
period – 3
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उत्तर
period – 3
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संबंधित प्रश्न
The position of eight elements in the Modern Periodic Table is given below where atomic numbers of elements are given in the parenthesis.
| Period No. | ||
| 2 | Li(3) | Be(4) |
| 3 | Na(11) | Mg(12) |
| 4 | K(19) | Ca(20) |
| 5 | Rb(37) | Sr(38) |
(i) Write the electronic configuration of Ca.
(ii) Predict the number of valence electrons in Rb.
(iii) What is the number of shells in Sr?
(iv) Predict whether K is a metal or a non – metal.
(v) Which one of these elements has the largest atom in size?
(vi) Arrange Be, Ca, Mg and Rb in the increasing order of the size of their respective atoms.
How does the number of valence electrons vary on moving from left or right in the first period of the periodic table?
How does the valency of elements change of moving from left to right in the third period of the periodic table?
An element X belongs to group 2 and another element Y belongs to group 15 of the periodic table:
(a) What is the number of valence electron in X?
(b) What is the valency of X?
(c) What is the number of valence electrons in Y?
(d) What is the valency of Y?
Explain how you have arrived at your answers.
Which of the following element would lose an electron easily?
(a) Mg
(b) Na
(c) K
(d) Ca
Which element has:
twice as many electrons in its second shell as in its first shell?
Use the letters only written in the Periodic Table given below to answer the questions that follow:
(a) State the number of valence electrons in the atom J.(b) Which element shown forms ions with a single negative charge?
(c) Which Metallic element is more reactive than R?
(d) Which element has its electrons arranged in four shells?
State the nature of compounds formed when group 17 elements combine with (i) metals (ii) non-metals.
Fill in the blank and rewrite the completed statement:
________ group in the periodic table contains elements that are all gases at room temperature.
The position of certain elements in the Modern Periodic Table is shown below:
| Group → Period ↓ |
1 | 2 | 3 to 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| 1 | G | H | |||||||
| 2 | A | I | B | C | |||||
| 3 | D | E | F |
Using the above table answer the following questions giving reasons in each case:
- Which element will form only covalent compounds?
- Which element is a non-metal with valency 2?
- Which element is a metal with valency 2?
- Out of H, C, and F which has the largest atomic size?
- To which family does H, C, and F belong?
