Advertisements
Advertisements
प्रश्न
Which among the following is the largest element?
विकल्प
Na
Mg
K
Ca
Advertisements
उत्तर
K
Explanation:
Atomic size generally increases down a group (as more electron shells are added) and decreases across a period from left to right (as the effective nuclear charge increases, pulling electrons closer).
- Na and Mg belong to Period 3, while K and Ca belong to Period 4. Therefore, K and Ca are larger than Na and Mg.
- Within Period 4, Potassium (K) is to the left of Calcium (Ca), meaning it has a lower effective nuclear charge and a larger atomic radius.
APPEARS IN
संबंधित प्रश्न
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with an explanation.
13Al, 14Si, 11Na, 12Mg, 16S
Which of the above elements has the highest metallic character?
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?
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.
What determines the chemical reactivity of elements?
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 |
Beryllium and calcium are alkaline earth metals.
Write a scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
Write a scientific reason.
In group 2, beryllium and calcium elements, calcium is more electropositive element than beryllium.
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
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.
- Which type of elements X and Y are metals, nonmetals or metalloids?
- From which block the elements X and Y are?
- Determine the electronic configuration and valency of these elements.
Make a chart which shows the name of the element, valency, atomic number, electronic configuration in the 2nd row of the modern periodic table and arrange these elements in ascending order of atomic mass.
What is the electronic configuration of K19?
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?
