What is the equivalent weight?
The first chemists defined the equivalent weight as the weight of one substance that would react with the second to form a third. As these chemists studied matter, they realized that the reactions have always occurred in the specified proportions. Many of their reaction components seemed to contribute the same level of activity, regardless of the fact that it was about the reaction.
The equivalent weight tables, based on hydrogen reactions, were compiled at the end of the 18th century. Hydrogen was used as a standard that was the least massive element; However, it does not respond easily with many elements. Easily cleaned and available metals are easily oxides oxides and were often used as an experimental basis for determining equivalent values.
This weight was measured, divided by eight and was reported as grams of equivalent hydrogen weight for this metal. Weight was divided by eight because oxygen reacts with hydrogen using eigpometer weight of htt-to-one for formationby the water. Oxygen was considered to be chemical opposite of hydrogen. Modern chemists would agree that oxygen is involved in oxidation reactions and hydrogen in reducing reactions.
This procedure worked well if the reaction was not too complex. Many metals have different oxides because they can achieve stable compounds in more than one valence configuration or oxidation state. When chemists learned more about the nature of the reactions they did, the periodic graph replaced the earlier tables.
Calculations performed by the equivalent weight of the table were followed by using molar materials. Molar refers to the number of atoms available to respond. The range of the reaction is based on this issue, not the weight of the reaction components. Mole of atoms has 6.023 x 10
The use of the hydrogen standard illustrates the difference. It is known that the water contains two hydrogen atoms per oxygen atom. Because oxygen has mOlar weight 16 grams per mol, while molar weight of hydrogen is 1 gram per mol, the ratio of matter is eight and one, oxygen to hydrogen. The mole ratio is two to one, hydrogen to oxygen, reflecting the actual composition.
Some chemistry fields continue to use equivalent weight in limited contexts. In chemistry on the basis of acid, the equivalent weight of a chemical species that reacts with 1 mola of hydronia (H o ) or 1 mol of hydroxide ions (oh +). In reducing oxidation reactions, the equivalent weight of the mass of the substance that receives or donates one mol of electrons is equivalent.
In the mining industry, the equivalent weights were used to describe the concentration of ore in the sample. For example, silver is asleep as a silver chloride from a liquid solution. The equivalent weight is the weight of silver chloride contains 1 gram of silver metal.
Polymeric chemists respond with long molecules with active side groups to form hard -to -library. AndTIVITY or reaction affinity can be measured in equivalent weights. An equally weighted resin creates the same degree of stretching in the same polymer families.