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Question & Answer Forum

Next time you have a doubt while studying, you know where to go. By simply posting your questions on Question & Answer Forum, you can have them answered by academic experts. You can also find related videos and explanations for better understanding.

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Swathi answered 4 year(s) , 1 month(s) ago

Atomic masses of first 30 elements?

It is not possible to give the atomic masses of all the elements. Here iam giving the atomic masses of first 30 elements in the periodic table.
Element Atomic number Atomic mass Hydrogen  1 1 Hel...

Asked by Mragisha

Dec 17

  • 1 Answer
  • 27 Likes
  • 113595 Views
Vikas answered 3 year(s) , 8 month(s) ago

Acidic & basic radicals.

Ans:  
The ion formed after removal of Hydrogen ion (H⁺ ion) from an acid is called acid radical.
Ex: When HCl loses H⁺ ion, it forms Cl⁻ which is an acid radical.
 
Following gi...

Asked by Sajjan singh

Nov 24

  • 4 Answers
  • 26 Likes
  • 97609 Views
Syeda answered 1 year(s) , 8 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 Mragisha

Dec 19

  • 4 Answers
  • 10 Likes
  • 62847 Views
Syeda answered 1 year(s) , 9 month(s) ago

Evaporation causes cooling.Explain the reason for this effect .Give 2 examples

Evaporation causes cooling because during evaporation the particle of the liqued absord energy from the surroundings to regain the energy lost during evaporation. the absorbtion of heat from the surrounding

...

Asked by Deepak

Sep 1

  • 4 Answers
  • 6 Likes
  • 61555 Views
Syeda answered 1 year(s) , 8 month(s) ago

Difference between solids,liquids and gases

Ans: Property Solids Liquids Gases

  1. Kinetic energy
Very low (negligible) medium Very High
  1. Rigidity
Highly rigid - Posses fixed shape Not rigid- gets the...

Asked by Najiha

Sep 6

  • 6 Answers
  • 7 Likes
  • 57280 Views
Ravinder answered 4 year(s) , 11 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
  • 6 Likes
  • 42981 Views
Syeda answered 10 month(s) , 3 day(s) ago

Sponge is solid but still it can be compressed.Why?

A sponge has minute holes,in which air is trapped, when we press it,the air is expelled out and we are able to compress it.sponge is a porous solid.but in other words the property of compressibility means an ob...

  • 3 Answers
  • 3 Likes
  • 37949 Views
Swathi answered 3 year(s) , 4 month(s) ago

For any substance, why does a temperature remains constant during the change of state?

The temperature of any substance remain constant during the change of state because the heat energy supplied is used up in changing the state of matter  and also this heat is used for breaking of several bonds...

Asked by Praveen

Sep 9

  • 1 Answer
  • 5 Likes
  • 32635 Views
Syeda answered 1 year(s) , 8 month(s) ago

Define a) Rigidity b) Fluidity c)Fluid d) Compressibilty e) Shape

Rigidity: The property of solids being stiff and resist towards stress is called rigidity. In solids – Rigidity is very high. In liquids – lower than solids but higher than gases. In gases – very low Fluidity:...

Asked by Nikhil

Jul 23

  • 2 Answers
  • 3 Likes
  • 32369 Views
Swathi answered 4 year(s) , 2 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
  • 3 Likes
  • 29203 Views
Agam answered 1 year(s) , 5 month(s) ago

Give one example of the diffusion of a solid in another solid .

Answer.

Diffusion in solid takes place , but at very low rate and takes a lot of time .. there is a good example - when you write on blackboard with chalk then , after 2~3 weeks you can observe...

Asked by Somnath

May 11

  • 5 Answers
  • 1 Like
  • 28853 Views
Satyanarayana answered 4 year(s) , 8 month(s) ago

Name one metal and one non-metal which exist as liquids at room tempereture.

Ans: Following are the metals and non-metals which exist in liquid state at room temperature. Metal Mercury Liquid State Non-metal...

Asked by Somnath

May 19

  • 1 Answer
  • 2 Likes
  • 28399 Views
Swathi answered 4 year(s) , 1 month(s) ago

All the important formulae relating with mole concept

HERE YOU SHOULD KNOW A FEW SYMBOLS.
n = no. of moles
N = no. of particles ( atoms, molecules, ions)
N 0 = avogadro constant ( 6.022 * 10 23)
m = mass...

Asked by Mragisha

Dec 15

  • 2 Answers
  • 1 Like
  • 24774 Views
Satyanarayana answered 3 year(s) ago

If one mole of carbon atom weighs 12g,what is the mass in grams of 1 atom of carbon

Mass of one mole of carbon atom = 12g

1 mole of a carbon contains 6.022 X 1023 atoms

Hence, mass of 6.022 X 1023 Atoms of carbon = 12g

Mass of 1 atom of carbon

...

Asked by Mragisha

Feb 5

  • 2 Answers
  • 4 Likes
  • 23616 Views
Dr satya answered 4 year(s) , 8 month(s) ago

Why does our palm feel cold when we put some acetone on it ?

Acetone is highly sublimable. it converts into vapour at a fast rate. this increases the liquid molecules around it in vapour phase thus our palm feel cold.

Asked by Somnath

Jun 4

  • 2 Answers
  • 4 Likes
  • 23580 Views
Syeda answered 1 year(s) , 8 month(s) ago

Boiling is Bulk Phenomenon

Answer.

Boiling is a bulk phenomenon. Particles of the bulk of the liquid gain enough energy to change to vapour state. The entire bulk of liquid and all the molecules including the interior and...

  • 3 Answers
  • 5 Likes
  • 23558 Views
Vikas answered 3 year(s) , 8 month(s) ago

State two characteristics of matter demonstrated by : a) diffusion b) brownian motion

a) Particles of matter have spaces between them. b) Particles of matter are in continuous motion.

Asked by Somnath

May 11

  • 2 Answers
  • 2 Likes
  • 23383 Views
Amarnathreddy answered 4 year(s) , 2 month(s) ago

Define latent heat of fusion?

latent heat of fusion is the amount of heat energy required to change 1Kg of solid to liquid

Asked by Dhiraj

Feb 28

  • 3 Answers
  • 4 Likes
  • 23279 Views
Satyanarayana answered 4 year(s) , 11 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
  • 22617 Views
Syeda answered 1 year(s) , 8 month(s) ago

Penultimate shell

Ans: The shell which is before the valence shell is called penultimate shell.
If ‘n’ is the valence shell then (n-1) is the penultimate shell.


Transition elements contain unpair...

Asked by Deb zyoti

Jul 23

  • 3 Answers
  • 2 Likes
  • 21360 Views
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