Gram Molar Volume

Any fundamental item (atoms, molecules, ions) present in the substance can be measured in moles. Similar to the concept of weight, a mole is used to measure the amount of a substance. ‘Mole’ was first used by a scientist in 1896, a German chemist named Wilhelm Ostwald. While carbon was once used to define the mole, it has been replaced. In other words, it’s the same mass of stuff containing the same number of essential constituents as a 12g sample of pure carbon contains atoms. Avogadro’s constant is now believed to be one mole rather than the previous notion of one mole. An individual mole consists of 6.023 x 10^23 distinct entities.

Avogadro’s number is a numerical constant applied to atoms, ions, or molecules, depending on the context. The Avogadro’s number is the same for all substances, but the molar mass varies. It is crucial to keep in mind when comparing molar masses. Atoms in elements can be varied in sizes and masses. Therefore, even though the quantity of entities is the same, the influence is different.

The Mole Concept Example

1) One litre of water contains approximately how many moles?

• The density of water is 1g/cc. One millilitre is equal to one cubic centimetre.
• The atomic weight of a molecule is equal to the mass of one mole (molar mass). Water has an atomic mass of 18.05 g in this region.
• We get= 1/ 18.05= 0.055 moles by inserting the mass of a substance and the molar mass.
• We know there are 0.055 moles in a millilitre of water, but the question asks for the number of moles in a litre of water, so we need to figure that out. We get 55.4 moles by multiplying the number of moles to 1000.
• In 1 litre of water, there are 55.04 moles present.
• One mole is equal to one gram molar mass

Application of Mole Concept

• On a macroscopic level, moles can be utilised to represent chemical reactions. 0.5 moles of oxygen and a mole of hydrogen gas are released when one mole of water decomposes.
• The molarity of a substance is determined using the mole concept. Solute molecular weight is measured in a solution by the number of moles of the solute present in the one-litre volume.
• The number of moles affects molality, as it does on molarity. The amount of moles in one kilogram of a solvent is meant by a substance’s molality.

Gram Molar Volume

The gram molar volume, commonly known as the molar volume, is an important term. The gram molar volume of an ideal gas at a given temperature and pressure is fixed or constant. For example, PV=nRT can be used to compute a compound’s gram molar volume.

To measure the volume of one mole of a gas at standard temperature and pressure (STP), we use the gram molar volume (GMV). Since the gram molecular mass of an ideal gas is fixed at STP, temperature and pressure are the primary determinants of gram molecular mass. The standard temperature is 273 degrees Kelvin, and the standard pressure is one atmosphere.

The ideal gas equation, PV=nRT, can compute the molar volume of an ideal gas.

PV=nRT

One can solve the equation by rearranging the numbers.

V=nRTP

N, R, T, and P, are the values to be applied to the equation.

V=n×0.0821×2731atm

Based on simplification,

V=22.4L

Therefore, the gram molar volume is 22.4L.

Note:

As a reminder, gram molecular volume (GMV) refers to the volume of one mole of a gas at a standard temperature and pressure (STP). Temperature and pressure also play a major role. 1 atm and 273K are the standard values for pressure and temperature. The ideal gas equation is used to get the gram molar volume, 22.4L.

Conclusion

A mole is a familiar unit of measure that measures the number of atoms and molecules in a bulk sample of matter. To put it another way, a mole is a unit of substance whose mass is equal to the mass in grams of pure 12C that contains exactly 12 atoms. For this unit, “mole” means “large mass,” which is consistent with the Latin connotation of the word. One of the most fundamental properties of matter, the number of atoms and molecules, is linked to a more easily observed macroscopic feature.

It’s important to note that while the term “mole” refers to an amount, it contains the same number of atoms in every element. However, because the masses of individual atoms fluctuate greatly, the 1-mole masses of various elements are not the same. It is the mass in grams of one mole of an element (or compound) represented in terms of grams per mole (g/mol).