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Swathi answered 4 year(s) , 3 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
  • 28 Likes
  • 121020 Views
Vikas answered 3 year(s) , 10 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
  • 27 Likes
  • 103357 Views
Syeda answered 1 year(s) , 10 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
  • 65957 Views
Satyanarayana answered 4 year(s) , 2 month(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
  • 5 Likes
  • 27416 Views
Swathi answered 4 year(s) , 3 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
  • 27390 Views
Saloni answered 2 year(s) , 1 month(s) ago

uses of ISOBARS

Isobars of uranium were used in nuclear reactor.
Isobars of cobalt were used in treatment of cancer.
Isobar of iodine was used in treatment of goitre.

Asked by Charvi

Oct 16

  • 8 Answers
  • 3 Likes
  • 21293 Views
Swathi answered 4 year(s) , 4 month(s) ago

How many oxygen atoms are present in 88 g of Carbon dioxide

Molar mass of CO2 = 44g/mol

Number of moles of CO2 present in 88g  of CO2 =  88g/44g mol-1

= 2 moles

1 mole of CO2 contains 2

...

Asked by Dhivyaa

Nov 23

  • 1 Answer
  • 1 Like
  • 19082 Views
Prasoon Kumar answered 4 year(s) , 3 month(s) ago

what is the difference between 2N and N2

2N represents two atoms of nitrogen whereas N 2 represents one molecule of nitrogen gas.

Asked by Kanishka

Nov 16

  • 2 Answers
  • 1 Like
  • 14698 Views
Swathi answered 4 year(s) , 1 month(s) ago

Calcium Carbonate (CaCO3) contains 40% calcium , 12% carbon and 48 % oxygen by mass.calculate the mass of the constituent elements in 2g of calcium carbonate

According to law of definite proportions, in a chemical substance, the elements are always present in definite proportions by mass.
Given data:
Percentage of Ca present in CaCO3 – 40%<

...

Asked by Navdeep

Feb 20

  • 1 Answer
  • 1 Like
  • 13773 Views
Satyanarayana answered 3 year(s) ago

Why metals are electropositive and non-metals are electronegative in nature?

metals have less than 4 electrons in their valence shell . hence its easier 2 give 1,2,3 electrons than 2 receive 5,6,7 electrons to complete d octet configuration.   eg. in Na no of electrons is 11 so valence...

Asked by Apurbo

Mar 21

  • 2 Answers
  • 1 Like
  • 12988 Views
Satyanarayana commented 5 year(s) , 3 month(s) ago

How many atoms are there in exactly 12g of carbon?

Ans:  Yes, it is possible to calculate the number of atoms present in 12 grams of carbon. For this it requires to find the number of moles of given substance.
Number of moles = given weight/ atomic weig...

Asked by Rajlakshmi

Jan 6

  • 1 Answer
  • 2 Likes
  • 11826 Views
Adithyan answered 3 year(s) ago

Symbols and names of elements derived from latin name

Name                           Latin Name                          Symbol

Potassium                    Kalium                                K
Soduim                        Natrium      ...

Asked by Adithyan

Feb 3

  • 4 Answers
  • 1 Like
  • 10244 Views
Swathi answered 4 year(s) , 3 month(s) ago

How many atoms of oxygen are present in 3oo grams of calcium carbonate

Molecular mass of calcium carbonate = 40 + 12 + 48 =100g

 1 mole of Calcium carbonate contains – 3 mole of oxygen atoms

100 g of Calcium carbonate contains - 3 X 6.022 X 1023 oxyge

...

  • 1 Answer
  • 0 Like
  • 10071 Views
Swathi answered 4 year(s) , 3 month(s) ago

What are the valencies of cuprous and cupric and ferrous and ferric

Some elements like copper and iron exhibits more than one valency. That is they have variable valencies.

Generally the name of the element end in 'ous' for lower valency and end in 'ic' for higher va

...

Asked by Perminder

Dec 21

  • 1 Answer
  • 0 Like
  • 9100 Views
Swathi answered 4 year(s) , 3 month(s) ago

How to find number of valence electrons using ionization energy?

Ans:

Ionization Energy is the minimum energy required to remove the outermost electron from a gaseous neutral atom to form a cation. 
The unit for ionization energy is electron volts or kilo jo

...

Asked by Shivani

Jan 5

  • 1 Answer
  • 0 Like
  • 8995 Views
Swathi answered 3 year(s) , 11 month(s) ago

How many moles of electron weighs 1 kg

Mass of electron = 9.1 x 10-31Kg

One mole of electrons = 6.023x1023

Mass of 1 mole of electrons = 6.023x1023 x 9.1 x 10-31Kg

How many moles

...

Asked by Yash

Apr 23

  • 1 Answer
  • 1 Like
  • 8164 Views
Swathi answered 3 year(s) ago

How to find valency of K2Cr2O7?

The combining capacity of an element is called its valency.
 or
The number of electrons lost, gained or shared by an atom of an element during chemical reaction for attaining stable electronic con...

Asked by Yash

Apr 8

  • 1 Answer
  • 0 Like
  • 7264 Views
Satyanarayana answered 4 year(s) , 3 month(s) ago

Atomic masses of some important elements That are Important of us.A chart of atomic masses

Ans: Following table gives the atomic mass of first 20 elements of the periodic table. These atomic masses are more useful for you.

Atomic number Symbol Element Name Atomic mass 1 H Hydrogen 1 2 H...

Asked by Mragisha

Dec 15

  • 1 Answer
  • 1 Like
  • 6969 Views
Swathi answered 4 year(s) , 3 month(s) ago

What is mole concept?

Mole is the measurement in chemistry. It is used to express the amount of a chemical substance.
One mole is defined as the amount of substance of a system which contains as many entities like, atoms, mo...

Asked by Mihir

Dec 25

  • 1 Answer
  • 1 Like
  • 6911 Views
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