Advertisements
Advertisements
प्रश्न
An element has its electron configuration as 2, 8, 2. Now answer the following question.
What is the group of this element?
The electronic configuration of an element is 2, 8, 2. Then write the answer to the question given below.
Which column does this element belong to?
Advertisements
उत्तर
The given electronic configuration is 2, 8, 2, which means it has 2 valence electrons in its outermost shell. The group (column) number of a main-group element is directly determined by its number of valence electrons.
APPEARS IN
संबंधित प्रश्न
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
3Li, 14Si, 2He, 11Na, 15P Which of these elements belong to be period 3?
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
1H, 7N, 20Ca, 16S, 4Be, 18Ar Which of these elements belong to the second group?
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
11Na, 15P, 17Cl, 14Si, 12Mg Which of these has largest atoms?
Write the scientific reason.
The third period contains only eight elements even though the electron capacity of the third shell is 18
An element has its electron configuration as 2, 8, 2. Now answer the following question.
What is the atomic number of this element?
An element has its electron configuration as 2, 8, 2. Now answer the following question.
Which of the following elements would this element resemble?
(Atomic numbers are given in the brackets)
N(7), Be(4), Ar(18), Cl(17)
______ is the outermost shell for elements of period 2.
Find the odd one out and give its explanation.
Answer the following question in one sentence.
Write the name of the noble gas having 2 electrons in its valence shell.
Answer the following question in one sentence.
Write the name of an element having electronic configuration 2,8,2.
Answer the following question in one sentence.
What determines the chemical reactivity of elements?
Match the columns.
| Column A | Column B |
| 1) Alkaline earth metals | a) Group 18 |
| 2) Alkali metals | b) Group 17 |
| 3) Halogen | c) Group 2 |
| 4) Noble gas | d) Group 1 |
| e) Group 14 |
The number of electrons in the outermost shell of an atom determines the ______.
Right or wrong sentence.
The valency of the elements in group 2 is 1.
Right or wrong sentence.
The elements lithium and beryllium are in the same period because their valencies are similar.
Complete the following chart.
| Shell | n | 2n2 | Electron holding capacity |
| K | 2 × 12 | 2 | |
| L | 2 | 8 | |
| 3 | 2 × 32 | 18 | |
| N | 4 | 2 × 42 |
Find the period in which these elements can be placed.
4Be, 17Cl, 2He, 13Al
Distinguish between:
Group - Period
Identify periods of elements and blocks of elements from given electronic configuration.
- 2, 8, 2
- 2, 8, 7
- 2, 1
