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Ravinder answered 5 year(s) , 3 month(s) ago

periodic table 1 to 30 plz give me with atmoic no. mass valency neutron proton and electronic configrution

sir these are given in book i want 21 to 30

Asked by Ravinder

Mar 9

  • 2 Answers
  • 7 Likes
  • 57071 Views
Swathi answered 4 year(s) , 6 month(s) ago

Postulates of Rutherford's model


Postulates of Rutherford nuclear model:

  • Positive charge is concentrated in the center of the atom, called nucleus.
  • Electrons revolve around the nucleus in circula
...

Asked by Adithyan

Nov 26

  • 1 Answer
  • 4 Likes
  • 32396 Views
Satyanarayana answered 5 year(s) , 3 month(s) ago

what are the limitations of thomson and rutherfords models? what is rutherford s nuclear model of an atom? what is average atomic mass ? how to find it ?

Ans:
  Ans:   According to JJ Thomson’s atomic model.

  • An atom is a positively charged sphere. Electrons are set within the sphere.
  • An atom is el
...

Asked by Kanishka

Feb 28

  • 1 Answer
  • 2 Likes
  • 24168 Views
Viraj commented 4 year(s) , 4 month(s) ago

what are isotopes and isobars ? with examples and in simple Language

Ans:   Isotopes: The atoms which posses same atomic number (the atoms same element) but different mass number are called Isotopes.
Ex: ...

Asked by Jaya

Nov 15

  • 2 Answers
  • 2 Likes
  • 23773 Views
Satyanarayana answered 4 year(s) , 4 month(s) ago

What is covalency and electrovalency?

Ans: Covalency: The number of electrons that an atom can shared to get stable electronic configuration is called it covalency.

Ex: In order to get stable Neon gas configurati

...

Asked by Archit

Jan 23

  • 1 Answer
  • 3 Likes
  • 19533 Views
Swathi answered 4 year(s) , 3 month(s) ago

Examples of isotopes and isobars.

Examples of Isotopes:
Isotopes of Hydrogen- Hydrogen – 1, Hydrogen – 2, Hydrogen - 3

Isotopes of Oxygen – Oxygen -16, Oxygen -17, Oxygen -18

Isotopes of Carbon – Carbon – 12, Carbon – 1

...

Asked by Prashoon

Feb 19

  • 1 Answer
  • 1 Like
  • 18275 Views
Abhishej answered 4 year(s) , 3 month(s) ago

if some other metal sheet will be used insted gold foil experiment of rutherford then what will be the observations

Gold was used because it is/was easy to roll into a thin film almost one atom thick. This can be done with other elements but require different processes which are a lot more expensive and time consuming and pr...

Asked by Harleen

Feb 23

  • 6 Answers
  • 0 Like
  • 16469 Views
Satyanarayana answered 4 year(s) , 3 month(s) ago

Limitations of Rutherford model, Bohr model,Thomson model.

Ans:
Draw backs of Thomson’s Model:
    •  It could not explain the stability of an atom, i.e how a positive charge in the atom holds the negatively charged electrons.
...

Asked by BAISHALI

Mar 11

  • 1 Answer
  • 1 Like
  • 15656 Views
Viraj commented 4 year(s) , 4 month(s) ago

Tricks to learn atomic masses first 20 elements

For your grade you need to remember atomic masses of first 20 elements.

The atomic mass is double the atomic number of an element. But it is not applicable for all the elements in the periodic table.

...

Asked by Aanya

Feb 4

  • 1 Answer
  • 1 Like
  • 7701 Views
Satyanarayana answered 5 year(s) , 2 month(s) ago

the raio by mass for calcium and oxygen in calcium oxide is 5:2.find ratio by number of atoms for calcium oxide.

Ans:
2Ca + O₂ → 2 CaO
80 grams of Calcium reacts with 32 grams of Oxygen in 5:2 ratio  to form 112 grams of Calcium Oxide.
Molecular weight of Calcium oxide = 56 grams
...

Asked by Nitish

Mar 12

  • 1 Answer
  • 0 Like
  • 7002 Views
Swathi answered 4 year(s) , 2 month(s) ago

Calculate molar mass of S8.

a) Sulphur is a poly atomic molecule. It is made up of 8 sulphur atoms.
Atomic mass sulphur atom = 32 g.
Molar mass of sulphur = 8 X 32 = 256 g.

b) (i) 32g of oxygen gas = 1 mole...

Asked by Adithyan

Mar 21

  • 1 Answer
  • 0 Like
  • 6655 Views
Satyanarayana answered 4 year(s) , 5 month(s) ago

what is the meaning / defination of absolute mass of electron & relative mass of electron ?

Ans: Absolute mass (actual mass) of electron is the mass of electron in grams. And relative mass of electron is the mass of electron  by comparing with the value 1/12th of mass of the carbon atom.

...

Asked by Garvita

Jan 2

  • 1 Answer
  • 0 Like
  • 6260 Views
Kopal answered 5 year(s) , 3 month(s) ago

A flask contains 4.4 g of Co2 gas calculate:How many atoms of oxygen are present in the given sample?

total mass = 12+16*2=44g
now mass of oxygen = 32/44 = 8/11g
hence n = 8*11/44=2 mol
therfore N= n*NA
N= 2*6.022 into 10's power 23
N= 1.2204*10's power 23.

Asked by Sunil dhikle

Mar 12

  • 2 Answers
  • 0 Like
  • 5825 Views
Swathi answered 4 year(s) , 1 month(s) ago

Define atomic mass and atomic number?

Atomic number
Atomic number (z) is the number of protons in an atom; it is also equal to the number of electrons in the atom.
Atomic number = Number of protons 
Example:...

Asked by Suruthika

May 7

  • 2 Answers
  • 0 Like
  • 5379 Views
Satyanarayana answered 5 year(s) , 4 month(s) ago

A compound was found to have the following percentage composition by mass Zn = 22.65% , S= 11.15%,H= 4.88% , O= 61.32%. The relative moliular mass is 287 g/mol. Find the molecular formula of the comp

Ans:        Zn S H O           22.65         11.15
           4.88
           61.32
  Step-1(Divide each element percentage with its atomic mass) 22.65/65= 0.34 11....

Asked by Sabu

Jan 13

  • 1 Answer
  • 1 Like
  • 4592 Views
Swathi answered 4 year(s) , 4 month(s) ago

Explain Thomson's model of an atom.

Thomson’s atomic model:    J.J. Thomson was the first to put forward a model to explain the structure of an atom.

Thomson's atomic model is also called water melon model or Christmas pudding mod...

Asked by Yashvardhan

Feb 1

  • 1 Answer
  • 0 Like
  • 4189 Views
Satyanarayana answered 4 year(s) , 3 month(s) ago

An element X forms the following compounds with hydrogen, carbon,and phosphorus:P2X3,P2X5,H2X2,H2X,CX2,CX. Find the valencies of X and othe..

Ans: 
P 2X 3:
Valence of Phosphorus = 3
Valence of X = 2
 
P 2 X 5 :
Valence of Phosphorus = 5
Valence of X  = 2...

Asked by Prashoon

Feb 17

  • 1 Answer
  • 0 Like
  • 3917 Views
Brahmananda answered 4 year(s) , 8 month(s) ago

solve by giving number

Na co3

Asked by Shahnawaz

Jan 27

  • 2 Answers
  • 1 Like
  • 3820 Views
Satyanarayana answered 5 year(s) , 4 month(s) ago

First 20 elements

Ans: Atomic number Symbol Element Name 1 H Hydrogen 2 He Helium 3 Li Lithium 4 Be Beryllium 5 B Boron 6 C Carbon 7 N Nitro...

Asked by Manthan

Feb 12

  • 2 Answers
  • 1 Like
  • 3444 Views
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