Why does atomic size (radius) decrease across a period?

Why does atomic size (radius) decrease across a period?
by

1 Answer

Answer :

The atomic radius decreases along a period because the atomic number increases by

one, but the additional electron goes to the same shell.There is no change in the number

of shells but more electrons make the nucleus to exert greater inward pull on the

electrons. As a result, outer electrons are pulled in closer to the nucleus which leads to

contraction of the atom and thus decrease in atomic size
by

Related questions

Atomic radius _moving from left to right across a period?

Description : Atomic radius _moving from left to right across a period?

Last Answer : Decreases

In the periodic table of elements, on moving from left to right across a period, the atomic radius – (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern

Description : In the periodic table of elements, on moving from left to right across a period, the atomic radius – (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern

Last Answer : (1) decreases Explanation: The atomic radius is the distance from the atomic nucleus to the outermost stable electron orbital in an atom that is at equilibrium. It tends to decrease across a period from ... usually increases while going down a group due to the addition of a new energy level (shell).

As one goes across a period in the periodic table, the ionization energy generally increases for one of the following reasons. Is it because of the increasing w) atomic radius x) melting point y) nuclear charge z) density

Description : As one goes across a period in the periodic table, the ionization energy generally increases for one of the following reasons. Is it because of the increasing w) atomic radius x) melting point y) nuclear charge z) density

Last Answer : ANSWER: Y -- NUCLEAR CHARGE

In the periodic table of elements, on moving from left to right across a period, the atomic radius (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern

Description : In the periodic table of elements, on moving from left to right across a period, the atomic radius (1) decreases (2) increases (3) remains unchanged (4) does not follow a definite pattern

Last Answer : increases

How the atomic size vary in a group and across a period? Explain with suitable example.

Description : How the atomic size vary in a group and across a period? Explain with suitable example.

Last Answer : How the atomic size vary in a group and across a period? Explain with suitable example.

Proceeding across a period in the Periodic Table, what atomic size trend is observed?

Description : Proceeding across a period in the Periodic Table, what atomic size trend is observed?

Last Answer : ANSWER: ATOMIC SIZE DECREASES

What is the element in period 4 with the smallest atomic radius?

Description : What is the element in period 4 with the smallest atomic radius?

Last Answer : What is the noble gas element with the largest radius

Among the elements of the 3rd period from Na to Ar, pick out the element: (L-2) (a). with highest first ionization enthalpy. (b). with largest atomic radius. (c). that is most reactive non-metal. (d). that is most reactive metal.

Description : Among the elements of the 3rd period from Na to Ar, pick out the element: (L-2) (a). with highest first ionization enthalpy. (b). with largest atomic radius. (c). that is most reactive non-metal. (d). that is most reactive metal.

Last Answer : (a). Ar has highest first ionization enthalpy. (b). Na has large atomic radius (covalent radius). (c). Cl is more reactive non-metal in 3rd period. (d). Na is most reactive metal in third period.

1The elements of the second period of the Periodic Table are given below: Li Be B C N O F (a) Give reason to explain why atomic radii decrease from Li to F. (b) Identify the most (i) metallic and (ii)non-metallic element. -Science

Description : 1The elements of the second period of the Periodic Table are given below: Li Be B C N O F (a) Give reason to explain why atomic radii decrease from Li to F. (b) Identify the most (i) metallic and (ii)non-metallic element. -Science

Last Answer : a) It is because nuclear charge increases due to increase in atomic number, therefore, force of attraction between nucleus and valence electrons increases, i.e. effective nuclear charge increases, hence ... element is ‘F’ because it can gain electrons easily due to smallest atomic size.

Atomic size refers to the ______ of an atom. (1) Radius (2) Circumference (3) Diameter (4) Centre

Description : Atomic size refers to the ______ of an atom. (1) Radius (2) Circumference (3) Diameter (4) Centre

Last Answer : (1) Radius Explanation: The term atomic size refers to the radius of an atom. The atomic size may be visualized as the distance between the centre of the nucleus and the outermost shell of an isolated atom.

Pick out the correct statement. (A) Loss of electrons from neutral atoms produces negative ions (B) The radius of nucleus & atomic size are of the order of 10 -12 cm & 10 - 8 cm respectively (C) Gain of electrons by neutral atoms form cations

Description : Pick out the correct statement. (A) Loss of electrons from neutral atoms produces negative ions (B) The radius of nucleus & atomic size are of the order of 10 -12 cm & 10 - 8 cm respectively (C) Gain of electrons by neutral atoms form cations

Last Answer : (B) The radius of nucleus & atomic size are of the order of 10 -12 cm & 10 - 8 cm respectivel

Taking first period and 17 th group of the periodic table, write gradation of properties with respect to the following: a) atomic size b) Ionisation energy c) electro positivity and electro negativity.

Description : Taking first period and 17 th group of the periodic table, write gradation of properties with respect to the following: a) atomic size b) Ionisation energy c) electro positivity and electro negativity.

Last Answer : The elements of 1 st period are hydrogen and helium. a) Atomic size of hydrogen is larger then that of helium because atomic size decreases across a period. b) Ionisation energy of helium ... higher as it increases down the group. Electro negativity of fluorine as it decreases down the group.

Referring to the periodic table of elements, it is found that with increasing atomic number. The atomic size in the same (A) Period increases (B) Period decreases (C) Group increases (D) Both 'b' & 'c'

Description : Referring to the periodic table of elements, it is found that with increasing atomic number. The atomic size in the same (A) Period increases (B) Period decreases (C) Group increases (D) Both 'b' & 'c'

Last Answer : Option D

The cause of periodicity of properties (a) Increasing atomic radius (b) Increasing atomic weights (c) Number of electrons in the valency orbit (d) The recurrence of similar outer electronic configuration

Description : The cause of periodicity of properties (a) Increasing atomic radius (b) Increasing atomic weights (c) Number of electrons in the valency orbit (d) The recurrence of similar outer electronic configuration

Last Answer : Ans:(d)

The repetition of property after a certain interval called ------? A. Electron efinity B. Atomic radius C. periodicity of property (Answer) D. none of these

Description : The repetition of property after a certain interval called ------? A. Electron efinity B. Atomic radius C. periodicity of property (Answer) D. none of these

Last Answer : C. periodicity of property (Answer)

Atomic radius of sodium 1.8 amstrong "..... How to determine this value ?

Description : Atomic radius of sodium 1.8 amstrong "..... How to determine this value ?

Last Answer : To determine the value, that is, to take the meter, you have to multiply it by 10 ^ -10 . (1.6 * 10 ^ - 10)

What is Atomic Radius ?

Description : What is Atomic Radius ?

Last Answer : Atomic radius measures the distance of the outer electron cell from the nucleus of the atom.

Calculate the drift velocity for the electrons in a silver wire which has a radius of 0.1 cm and carries a current of 2 A. Atomic mass of silver=108 a

Description : Calculate the drift velocity for the electrons in a silver wire which has a radius of 0.1 cm and carries a current of 2 A. Atomic mass of silver=108 a

Last Answer : Calculate the drift velocity for the electrons in a silver wire which has a radius of 0.1 cm and carries a ... silver `=10.5xx10^(3) kg//m^(3)`.

A beam of ultraviolet radius hacking wavelength between `100nm and 200nm` is inclined on a sample of atomic hydrogen gas. Assuming that the atoms are

Description : A beam of ultraviolet radius hacking wavelength between `100nm and 200nm` is inclined on a sample of atomic hydrogen gas. Assuming that the atoms are

Last Answer : A beam of ultraviolet radius hacking wavelength between `100nm and 200nm` is inclined on a sample of ... being observed by on atom in the ground state

What shell will determine the atomic radius of carbon?

Description : What shell will determine the atomic radius of carbon?

Last Answer : Feel Free to Answer

Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has – (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge

Description : Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has – (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge

Last Answer : (3) stable half filled 2p sub level Explanation: Ionization energy is a measure of the ease in which atoms lose electrons and become positive ions.

The ratio of atomic radius to its nuclear radius is about (A) 10 5 (B) 10 8 (C) 10 12 (D) 10 15

Description : The ratio of atomic radius to its nuclear radius is about (A) 10 5 (B) 10 8 (C) 10 12 (D) 10 15

Last Answer : (A) 10

Atomic __________ is a whole number for an element. (A) Number (B) Weight (C) Radius (D) None of these

Description : Atomic __________ is a whole number for an element. (A) Number (B) Weight (C) Radius (D) None of these

Last Answer : (A) Number

Atomic __________ of an element is a whole number. (A) Weight (B) Number (C) Volume (D) Radius

Description : Atomic __________ of an element is a whole number. (A) Weight (B) Number (C) Volume (D) Radius

Last Answer : (B) Number

Which of the following has the smallest atomic radius? w) iodine x) chlorine y) fluorine z) bromine

Description : Which of the following has the smallest atomic radius? w) iodine x) chlorine y) fluorine z) bromine

Last Answer : ANSWER: Y -- FLUORINE

Of the following elements which has the largest atomic radius? w) Ba x) F y) C z) Be

Description : Of the following elements which has the largest atomic radius? w) Ba x) F y) C z) Be

Last Answer : ANSWER: W -- Ba

Which of the following four elements has the largest atomic radius? Is it: w) strontium x) francium y) calcium z) bromine

Description : Which of the following four elements has the largest atomic radius? Is it: w) strontium x) francium y) calcium z) bromine

Last Answer : ANSWER: X -- FRANCIUM

Which halogen has the largest atomic radius:

Description : Which halogen has the largest atomic radius:  

Last Answer : ANSWER: ASTATINE

The halogen with the largest atomic radius is: w) Cl x) I y) Br z) At

Description : The halogen with the largest atomic radius is: w) Cl x) I y) Br z) At

Last Answer : ANSWER: Z -- At

Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge

Description : Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge

Last Answer : stable half filled 2p sub level

Shear stress in a fluid flowing in a round pipe (A) Varies parabolically across the cross-section(B) Remains constant over the cross-section(C) Is zero at the centre and varies linearly with the radius(D) Is zero at the wall and increases linearly to the centre

Description : Shear stress in a fluid flowing in a round pipe (A) Varies parabolically across the cross-section (B) Remains constant over the cross-section (C) Is zero at the centre and varies linearly with the radius (D) Is zero at the wall and increases linearly to the centre

Last Answer : (C) Is zero at the centre and varies linearly with the radius

Applying a pressure drop across a capillary results in a volumetric flow rate 'Q' under laminar flow conditions. The flow rate for the same pressure drop, in a capillary of the same length but half the radius is (A) Q/2 (B) Q/4 (C) Q/8 (D) Q/16

Description : Applying a pressure drop across a capillary results in a volumetric flow rate 'Q' under laminar flow conditions. The flow rate for the same pressure drop, in a capillary of the same length but half the radius is (A) Q/2 (B) Q/4 (C) Q/8 (D) Q/16

Last Answer : (D) Q/16

In an ideal tubular-flow reactor (A) There is no mixing in longitudinal direction (B) Mixing takes place in radial direction (C) There is a uniform velocity across the radius (D) All (A), (B) and (C)

Description : In an ideal tubular-flow reactor (A) There is no mixing in longitudinal direction (B) Mixing takes place in radial direction (C) There is a uniform velocity across the radius (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Heat flow across a hollow sphere of inner radius 'r1' and outer radius 'r2' is directly proportional to (A) (r2- r1)/r1. r2 (B) r1. r2/(r2- r1) (C) (r2 + r1)/r1. r2 (D) r1. r2/(r2 + r1)

Description : Heat flow across a hollow sphere of inner radius 'r1' and outer radius 'r2' is directly proportional to (A) (r2- r1)/r1. r2 (B) r1. r2/(r2- r1) (C) (r2 + r1)/r1. r2 (D) r1. r2/(r2 + r1)

Last Answer : (B) r1. r2/(r2- r1)

If the radius of blood vessels decrease, what will be in the blood pressur? -Do You Know?

Description : If the radius of blood vessels decrease, what will be in the blood pressur? -Do You Know?

Last Answer : answer:

The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

Description : The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

Last Answer : The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

If the radius of blood vessels of a person decreases his/her blood pressure will (1) increase (2) decrease (3) remain unaffected (4) increase for males and decrease for females

Description : If the radius of blood vessels of a person decreases his/her blood pressure will (1) increase (2) decrease (3) remain unaffected (4) increase for males and decrease for females

Last Answer : (1) increase Explanation: An obese person has a greatly increased number of blood vessels because of the amount of adipose tissue that must be serviced. As a result, the total length of his or ... words, the smaller the diameter of the vessel, the greater the resistance it offers to blood flow.

Upto the critical radius of insulation, added insulation, will (A) Increase the heat loss (B) Decrease heat loss and will have no effect beyond that (C) Decrease heat flux (D) Reduce convection heat loss compared to conduction heat less

Description : Upto the critical radius of insulation, added insulation, will (A) Increase the heat loss (B) Decrease heat loss and will have no effect beyond that (C) Decrease heat flux (D) Reduce convection heat loss compared to conduction heat less

Last Answer : Option B

If the radius of blood vessels decrease,what will be in the blood pressur?

Description : If the radius of blood vessels decrease,what will be in the blood pressur?

Last Answer : Increase

the radius of blood vessels decrease,what will be in the blood pressur?

Description : the radius of blood vessels decrease,what will be in the blood pressur?

Last Answer : Increase

How can the pilot increase the rate of turn and decrease the radius at the same time? a. Shallow the bank and increase airspeed b. Steeper bank and increase airspeed c. Steeper bank and decrease airspeed

Description : How can the pilot increase the rate of turn and decrease the radius at the same time? a. Shallow the bank and increase airspeed b. Steeper bank and increase airspeed c. Steeper bank and decrease airspeed

Last Answer : c. Steeper bank and decrease airspeed

Newton’s rings experiment is performed and radius (or diameter) is calculated. Now Plano-convex lens is replaced with another Plano-convex lens of greater Radius of curvature. What will be effect on radius (or diameter)? (a) Radius (or diameter) will remain constant but there will be more brightness (b) Radius (or diameter) will increase (c) Radius (or diameter) will decrease (d) There will be no effect

Description : Newton's rings experiment is performed and radius (or diameter) is calculated. Now Plano-convex lens is replaced with another Plano-convex lens of greater Radius of curvature. What will be effect on radius ( ... ) will increase (c) Radius (or diameter) will decrease (d) There will be no effect

Last Answer : (b) Radius (or diameter) will increase

Newton’s rings experiment is performed with air gap between lens and plate. Now that gap is filled with water. What will be effect on radius (or diameter)? (a) Radius (or diameter) will remain constant but there will be more brightness (b) Radius (or diameter) will increase (c) Radius (or diameter) will decrease (d) There will be no effect

Description : Newton's rings experiment is performed with air gap between lens and plate. Now that gap is filled with water. What will be effect on radius (or diameter)? (a) Radius (or diameter) will remain ... or diameter) will increase (c) Radius (or diameter) will decrease (d) There will be no effect

Last Answer : (c) Radius (or diameter) will decrease

In Newton’s rings experiment, if monochromatic source of light is replaced by another monochromatic source of higher wavelength. What will be the effect on radius (or diameter)? (a) Radius (or diameter) will decrease (b) Radius (or diameter) will increase (c) There will be no effect (d) Radius (or diameter) will remain constant but there will be more brightness

Description : In Newton's rings experiment, if monochromatic source of light is replaced by another monochromatic source of higher wavelength. What will be the effect on radius (or diameter)? (a) Radius (or ... be no effect (d) Radius (or diameter) will remain constant but there will be more brightness

Last Answer : (b) Radius (or diameter) will increase

If the radius of blood vessels of a person decreases his/her blood pressure will (1) increase (2) decrease (3) remain unaffected (4) increase for males and decrease for females

Description : If the radius of blood vessels of a person decreases his/her blood pressure will (1) increase (2) decrease (3) remain unaffected (4) increase for males and decrease for females

Last Answer : increase

Decrease in atomic number is observed during a)`alpha`-emission b)`beta`-emission c)positron emission d)electron capture

Description : Decrease in atomic number is observed during a)`alpha`-emission b)`beta`-emission c)positron emission d)electron capture

Last Answer : Decrease in atomic number is observed during a)`alpha`-emission b)`beta`-emission c)positron emission ... `-emission C. positron emission D. K-capture

A nuclide has mass number (A) and atomic number (Z). During a radioactive process if: (A) both A and Z decrease, the process is called `alpha`-decay (

Description : A nuclide has mass number (A) and atomic number (Z). During a radioactive process if: (A) both A and Z decrease, the process is called `alpha`-decay (

Last Answer : A nuclide has mass number (A) and atomic number (Z). During a radioactive process if: (A) both A and Z decrease, ... 4 C. 1,3, and 4 D. 1,2, and 4

The decrease in the atomic number is not observed in case of (A) Electron capture (B) β-emission (C) α-emission (D) Positron emission

Description : The decrease in the atomic number is not observed in case of (A) Electron capture (B) β-emission (C) α-emission (D) Positron emission

Last Answer : (B) β-emission

When a radioisotope undergoes beta minus decay, does its atomic number: w) increase x) decrease y) remain the same z) vary depending on the element involved

Description : When a radioisotope undergoes beta minus decay, does its atomic number: w) increase x) decrease y) remain the same z) vary depending on the element involved

Last Answer : ANSWER: W -- INCREASE

If voltage across a bulb rated 220 volt-100 watt drops by `2.5 %` of its value, the percentage of the rated value by which the power would decrease is

Description : If voltage across a bulb rated 220 volt-100 watt drops by `2.5 %` of its value, the percentage of the rated value by which the power would decrease is

Last Answer : If voltage across a bulb rated 220 volt-100 watt drops by `2.5 %` of its value, the percentage of the rated value ... 20%` B. `2.5%` C. `5%` D. `10%`