Question

1 g equivalent of a substance is the weight of that amount of a substance which is equivalent to:

Answer 1

Hint: We know that the concept of mole is based on molecular weight. Gram equivalent (or) gram equivalent weight would be based on the equivalent concept. We have to know that mass of one gram equivalent is equal to mass measures in grams that would numerically equal to equivalent weight. We can define equivalent weight as the mass of an element/ion/compound that combines/displaces one part of hydrogen, eight parts of oxygen by mass.

Complete step by step answer:
1 g equivalent of a substance is the weight of that amount of a substance which is equivalent to gram equivalent mass.
We can define the equivalent weight of an element as the atomic weight divided by valence electrons in compounds. Its unit is atomic mass unit, the amount of substance in gram is equal to the equivalent weight known as the gram equivalent weight.
For example, hydrogen has atomic weight of 1.008 and the valence electron in hydrogen is 1, so its equivalent weight is 1.008.
We can define gram equivalent mass as the mass of one mole of element, ion, molecule divided by their electrons shared or their valences.
Gram equivalent mass is generally defined for metals (or) salts (or) ions (or) for the compounds/atoms/molecules which have the ability to form ions.
Let us take another example of aluminum trichloride.
The molar mass of aluminum trichloride is 133.34 g/mol.
We can calculate the equivalent mass as follows,
Equivalent mass = $\dfrac{{{\text{Atomic}}\,{\text{weight}}}}{{{\text{Number}}\,{\text{of}}\,{\text{electrons}}\,{\text{shared}}}}$
Equivalent mass = $\dfrac{{{\text{133}}{\text{.34}}\,{\text{g/mol}}}}{{\text{3}}}$
Equivalent mass = ${\text{44}}{\text{.44 g/eq}}$

Note:
For elements that have more than one valency in forming compounds contains more than one equivalent weight.
For example, if iron has a valence of three, then equivalent weight would be 18.615 g/eq. If iron has a valence of two, then equivalent weight would be 27.9225 g/eq.
We are calculating the values of equivalent weight using the atomic mass of iron (55.854 g) and the number of electrons shared.
The equivalent weight is used to determine the weight proportion in which is combined to form compounds. We can use equivalent weight in volumetric and gravimetric analysis. We can also use it in polymer chemistry.