Advertisements
Advertisements
प्रश्न
Give scientific reasons for the following:
Atomic radius goes on decreasing while going from left to right in a period.
Give scientific reasons:
While going from left to right within a period, the size of the atom decreases.
Advertisements
उत्तर
- While going from left to right within a period, the atomic number increases one by one, meaning the positive charge on the nucleus increases by one unit at a time.
- However, the additional electron gets added to the same outermost shell. Due to the increased nuclear charge, the electrons are pulled towards the nucleus to a greater extent, and thereby the size of the atom decreases.
APPEARS IN
संबंधित प्रश्न
Arrange the following as per the instruction given in the bracket:
Mg, Cl, Na, S, Si (decreasing order of atomic size).
Give the trends in atomic size on moving down the group.
Which is greater in size an atom or a cation?
Study the radius of the element given below and answer the following questions.
| elements | K | Na | Rb | Cs | Li |
| Atomic radius (pm) | 231 | 186 | 244 | 262 | 151 |
a) Which of the above elements have the smallest atom?
b) In which group of the modern periodic table the above element are belongs?
c) What is the periodic trend observed in the variation of atomic radii down a group?
With reference to the variation of properties in the Periodic Table, which of the following is generally true?
Atomic size increases from left to right across a period.
On moving from left to right in a periodic table, the size of the atom _______.
_______ is the distance between the nucleus of the atom and its outermost shell.
While going from top to bottom in a group the atomic radius _______.
The size of an atom depends on the number of valence electrons.
Write scientific reason.
In same period, boron and oxygen elements have different atomic size.
Which of the following gives the correct increasing order of the atomic radii of O, F, and N?
Elements have been arranged in the following sequence on the basis of their increasing atomic masses.
| F, | Na, | Mg, | Al, | Si, | P, | S, | Cl, | Ar, | K |
- Pick two sets of elements which have similar properties.
- The given sequence represents which law of classification of elements?
Arrange the following elements in increasing order of their atomic radii.
- Li, Be, F, N
- Cl, At, Br I
Atomic number of a few elements are given below
10, 20, 7, 14
- Identify the elements
- Identify the Group number of these elements in the Periodic Table
- Identify the Periods of these elements in the Periodic Table
- What would be the electronic configuration for each of these elements?
- Determine the valency of these elements
- Electropositive nature of the element(s) increases down the group and decreases across the period
- Electronegativity of the element decreases down the group and increases across the period
- Atomic size increases down the group and decreases across a period (left to right)
- Metallic character increases down the group and decreases across a period.
On the basis of the above trends of the Periodic Table, answer the following about the elements with atomic numbers 3 to 9.
- Name the most electropositive element among them
- Name the most electronegative element
- Name the element with smallest atomic size
- Name the element which is a metalloid
- Name the element which shows maximum valency.
The diagram below shows part of the periodic table.
- Which elements would react together to form covalent compounds?
- Between the two elements W and Z, which will have a bigger atomic radius? Why?
An element with the largest atomic radius among the following is ______.
Arrange the following as per the instruction given in the bracket:
Carbon, Fluorine, Beryllium (decreasing order of atomic size).
Which one has the largest size?
