System & Device Check
About the Class
Theory and problems of mole concept will be discussed. Useful to students studying chemistry in GCSE - O/A level, IIT-JEE/AIEEE preparatory level , CBSE and any State of Indian board of syllabus.
Concept – 1 - Mole
One mole of any substance contains
That is Avogadro’s number
represented by 6.022 x 10^23
What is a mole?
A unit which has a mass equal to the relative atomic mass or relative molecular mass or formula mass.
A simple equation:
n = w/A or w/M
n = number of moles of the given substance or element
w = mass of the given substance
A = relative atomic mass of the element
M = relative molecular mass of the substance
Calculate the mole of the substances given below.
(a) 16 g of O2 and 14 g of N2
(b) 8 g of O2 and 22 g of CO2
(c) 28 g of N2 and 22 g of CO2
(d) 32 g of O2 and 32 g of N2
Concept – 2 – Number of molecules / atoms
Based on Avogadro’s number we can count the number of molecules present in a given mass of a substance.
n’ = N x n
n’ = number of molecules or atoms
N = Avogadro’s number
n = mole
Calculate the number of molecules of carbon dioxide in 440 g carbon dioxide gas at S.T.P.
Language of instruction:
Keywords: mole concept, avogadro's number, chemistry problems