Calculation of edge length and radius of atom.

Calculate the radius of copper atom if it crystallise in face centred cubic lattice and has a density of 8.93 g / cm cube. Solution Structure given = fcc For fcc , Z = 4 Density , d = 8.93 Molar mass , M = 63.55 Avogadro number = 6.2×10^23 Use the given formula InContinue reading “Calculation of edge length and radius of atom.”

How many atoms are there in 1 gram of carbon?

For  calculation of number of atoms we have to calculate the number of moles present in 1gram carbon. Multiply the number of moles with Avogadro number. Step I  Number of moles in 1 gram of carbon = given mass / molar mass Molar mass (molecular or atomic mass expressed in grams) = 12g So theContinue reading “How many atoms are there in 1 gram of carbon?”

How many oxygen atoms are there in 90g of H2O molecule?

1 molecule of H2O has 1 atom of oxygen. Firstly we will calculate the number of atoms in 90g of H2O. we will explain it in two steps:- Step I:- No.of moles of H2O = given mass / molar mass No. of moles = 90/18 = 5 moles No. Of molecules = No. of molesContinue reading “How many oxygen atoms are there in 90g of H2O molecule?”

What is the number of moles of O-atom in 126 AMU of HNO3?

Here we have 126 AMU of HNO3, Molar mass of HNO3 is 1+14+16×3 = 63amu Number of molecules of HNO3 are = 126/63 = 2 Here we have 2 molecules Each molecule have 3 atoms of oxygen. So no. of oxygen atoms= 3×2 =6 atoms No. Of moles = given particles/ avogadro number No. ofContinue reading “What is the number of moles of O-atom in 126 AMU of HNO3?”

How does the normality of a mixture equation change for different solutes?

Actually normality depends upon a simple formula that is :- Normality = Number of Gram equivalents / litre The term gram equivalents change as the valency of a substance changes . all the elements do not have same valence and hence it varies from element to element or molecule to molecule. And the term gramContinue reading “How does the normality of a mixture equation change for different solutes?”

what is valency ? how to calculate it?

Valency :- “It is the combining capacity of an atom”. it also indicates the number of electrons that can be gained , lost or shared . It decides that how many bonds can be formed, it gives the idea of molecule formation and the type of bond formed. calculation of valency is a simple taskContinue reading “what is valency ? how to calculate it?”

How to find a lone pair in simple way?

Step 1: write the configuration of element and then show the valence elactrons around the symbol of element . Step2: make the bonds around the atom according to its valency and use the electrons for making the bonds. Step3: Now see if there are any unshared electrons pairs. These are your lone pairs. See theContinue reading “How to find a lone pair in simple way?”