How to Make Use of the Mole Concept in Numerical Problems – Part 1

Mole is a quantity proportional to the number of elementary entities of a substance.


Since equal volumes of all gases, at the same temperature and pressure, have the same number of molecules according to the Avogadro’s law, molar volumes (22.4 L or dm3) of all gases, at the standard (normal) temperature and pressure (STP; 00C (or 273 K) & 1 atm respectively), have the same number of molecules (NA = 6.022 x 1023).

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The mole concept applies to molecules, ions, ion pairs, atoms, electrons.
Question:
Calculate the total number of electrons present in 1.6 g of Methane (CH4) & the total number of neutrons present in 7 mg of 14C.
Solution:



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Mind-blowing moles❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

References:

(1)    Brown, C.; Ford, M. Higher Level Chemistry, 2nd ed.; Pearson Education: Harlow, Essex, 2014.

‌(2)    Ncert. Chemistry : Textbook for Class XI - Part.I; National Council Of Educational Research And Training: New Delhi.

(3)    Wikipedia Contributors. Mole (unit). Wikipedia. https://en.wikipedia.org/wiki/Mole_(unit).

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