Advertisements
Advertisements
प्रश्न
Observe the periodic table given below and write the answers of the questions.

- Write the name and valencies of the elements in 3rd row.
- Classify the elements in this row as metal, nonmetal and metalloids.
- Which block does nonmetals belong to?
- Write name of any two metalloid elements.
Advertisements
उत्तर
- The elements in the third period are Sodium, Magnesium, Aluminium, Silicon, Phosphorus, Sulphur, Chlorine and Argon.
Their valencies are 1, 2, 3, 4, 3, 2, 1 and 0 respectively. - Sodium (Na), Magnesium (Mg) and Aluminium (Al) are metals. Silicon (Si) is a metalloid.
Phosphorus (P), Sulphur (S) and Chlorine (Cl) are nonmetals. Argon (Ar) is an inert gas element and is not classified as a metal, nonmetal or metalloid. - Nonmetals belong to p-block.
- Two metalloid elements: Silicon and Germanium.
APPEARS IN
संबंधित प्रश्न
An element has its electron configuration as 2, 8, 2. Now answer the following question.
a. What is the atomic number of this element?
b. What is the group of this element?
c. To which period does this element belong?
d. With which of the following elements would this element resemble? (Atomic numbers are given in the brackets)
N(7), Be(4), Ar(18), Cl(17)
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.
4Be, 6C, 8O, 5B, 13Al Which is the most electropositive element among these?
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
19K, 3Li, 11Na, 4Be Which of these atoms has smallest atomic radius?
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 questions.
i. What is the atomic number of this element?
ii. What is the valency of this element?
iii. What is the group of this element?
iv. To which period does this element belong?
v. With which of the following elements would this element resemble?
`_7N , _4Be , _18Ar , _17CL`
An element has its electron configuration as 2, 8, 2. Now answer the following question.
What is the group of this element?
An element has its electron configuration as 2, 8, 2. Now answer the following question.
To which period does this element belong?
An element has its electron configuration as 2, 8, 2. Now answer the following question.
With which of the following elements would this element resemble?
(Atomic numbers are given in the brackets)
N(7), Be(4), Ar(18), Cl(17)
Which pair of atomic numbers represents elements in the same group?
Which among the following elements would lose an electron easily?
Match the columns.
| Column A | Column B |
| 1) s -block | a) Lanthanides and actinides |
| 2) p -block | b) Group 3 to 12 |
| 3) d -block | c) Group 1, 2 |
| 4) f -block | d) Group 13 to 18 |
| e) Zero group |
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 valency of the elements in group 2 is 1.
Write an Explanation.
Group
Write scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
Identify periods of elements and blocks of elements from given electronic configuration?
- 2, 8, 2
- 2, 8, 7
- 2, 1
XY compound is formed by X (Atomic number 11) and Y (Atomic number 17), then answer the questions given below.
- Determine the position of the element X and Y periodic table.
- X and Y belongs to which of the following: metals, nonmetals or metalloids?
- From which block the elements X and Y are?
- Determine the electronic configuration and valency of these elements.
An element has its electron configuration as 2, 8, 1. Now answer the following questions:
- What is the atomic number of this element?
- What is the group of this element?
- To which period does this element belong?
