What do you understand about a mole?
It is essential to consider quantities of substances regarding the number of atoms, ions, or molecules present in routine chemical problems. The unit devised by chemists to express the number of atoms or ions or molecules is called the mole (mol).
One mole is said to be gram atomic mass or gram molecular mass or gram formula mass of any substance, like atoms molecules or ions containing 6.02 x 1023 particles.
The purpose of relating the unit number of particles to the standard atomic masses is to provide a ready method of calculating the mass of a mole of any substance (molar mass).
Let us consider one mole of carbon-12 atoms and one mole of magnesium atoms. By definition, a mole of C-12 is 12 g of this substance. The atomic mass of magnesium is 24, which means each atom of magnesium is twice as heavy as a carbon atom; it follows that the mole of magnesium is 24 g. Similarly, a mole of oxygen atoms is 16 g, and a mole of oxygen molecules is 32 g.
Modern experimental methods for determining atoms, molecules, and ions show that in one gram mole of a substance, there are 6.02 x 1023 particles. This vast number is called the Avogadro's Number. It is given in honor of Amadeo Avogadro (1776-1856). It is denoted by NA.
In the light of Avogadro's number, mole is comprehensively defined as the mass in grams of atoms or molecules or ions (gram atomic mass or gram molecular mass or gram formula mass) which contains Avogadro's number of particles (6.02 x 1023).
For Example:
A mole of hydrogen atom = 1 g = 6.02 x 1023 atoms
A mole of hydrogen molecule = 2 g = 6.02 x 1023 molecules
A mole of NaCI = 58.5 g = 1 mole Na+ + 1 mole Cl-
A mole of NaCI = 58.5 g = 6.02 x 1023 Na+ + 6.02 x 1023 Cl-
A mole of H2O = 18g= 6.02 x 1023 molecules
2 moles of H2O = 36g = 2 x 6.02 x 1023 = 1.2046.02 x 1024 molecules
How to calculate the Number of Moles?
The mole is a standard and the fundamental unit for the physical quantity 'amount of substance' in the provided sample. As discussed earlier, a mole is a numeral value that equals 6.02 x 1023 particles; also, we can call it Avogadro's constant. These particles can be atoms, molecules, electrons, protons, neutrons, etc. If we have an almond box containing approximately 6.022 x 1023 almonds, we can say that we have 1 mole of almonds in that particular box.
So if you want to calculate the amount of moles existing in any substance, you will divide the given weight of the substance by the substance's molar mass.
Mathematical Representation:
num: of moles = given mass of substance / molar mass of a substance
n = m / M
Example
What is the number of moles in 25.0 grams of water?
Data:
Molar Mass, M, of H2O = 18.0 gm / mol
Given mass, m, of H2O = 25.0 gm
No of Moles, n, of H2O = ?
Solution:
In order to find the number of moles, we will have to use the following formula
n = m / M
n = 25.0 (gm) / 18.0 (gm/mol)
Number of moles, n = 1.39 mol
What tool is best for calculating the number of moles?
Tools City’s Mole Calculator is one of the best tools you will ever find on the internet.Tools City's Mole Calculator is one of the easiest tools to figure out number of moles. It also provides you the conversion facility; you do not need to convert mass in grams into the mass in micrograms, nanograms, milligrams, etc. Tools City’s Mole Calculator is available in two modes: simple mode and advanced mode. In simple mode, you will find three parameters; mass, molecular weight, and the number of moles, while advanced mode will provide you with one more parameter of the number of molecules. No other tool on the internet will provide these facilities.
How to use Tools City’s Mole Calculator?
The use of Tools City's Mole Calculator is as easy as ABC. All you need a laptop or a mobile or a tablet along with access to the internet. Following are the few steps for using the Mole Calculator:
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Visit Tools City's Mole Calculator and go to Mole Calculator.
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You will see the calculator with simple mode by default. You can also use the advanced mode if the values are given in those parameters. There will be three boxes; the first for mass, the second for molecular weight, and the third for the number of moles.
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You will place the values for any two parameters; for example, you put mass as 1 gram, and the molecular weight is 2 gram per mole; you will now see the result in the number of moles as 0.5 moles.
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If you are using the advanced mode, you will see four boxes: mass, molecular weight, number of moles, and number of molecules. In the advanced mode, the process is the same; just put any two values, you will get to know the values of the other two as results.
You can have the access to change the units of parameters in Tools City's Mole calculator. The mass has the units in nanograms (ng), micrograms (µg), milligrams (mg), grams (g), decagrams (dag), kilograms (kg), metric tons (t), ounces (oz), pounds (lb), stones (stone), US short, tons (US ton), imperial tons (Long ton) and atomic mass unit (u). The number of moles has the units in moles (mol), millimoles (mmol), micromoles (μmol), nanomoles (nmol), and picomoles (pmol).