in case of dimerisation which of the following is incorrect. 1) Abnormal molar mass is greater than actual molar mass. 2) Vant Hoff factor is less than one. 3) Abnormal collagative property is greater than normal collagative property. 4) All of these
Answers
Explanation:
<Introduction to Abnormal Molar Masses
To understand the abnormal molar masses, first, we need to understand the total number of particles left either after the association or dissociation of the solute molecules present in a solution or a solvent. To study and understand more about more about the abnormalities, Dutch chemist Van’t Hoff, discovered (i), which is known as the Van’t Hoff’s factor.
a solution, some solute molecules start to associate with each other. Thus, now there is less number of these particles inside a solution. The colligative properties will vary with a number of solute particles in the solution. As a result, they will now, start to decrease with the number of solute particles being less.
The molecular mass of the solute is inversely proportional to its colligative properties. Thus a decrease in colligative properties will lead to an increase in the molecular masses.
Example: acetic acid or ethanoic acid associate in the solution, when dissolved in benzene, dimerizes, because the number of particles and hydrogen bondings are reduced
In case of dimerisation, the incorrect option is:
(3) Abnormal collagative property is greater than the normal collagative property.
- Abnormal molar mass is always greater in dimerisation because two molecules are joining to form one.
- Vant Hoff factor is always less than due to less no of molecules after dimerisation.
- Abnormal collagative property is calculated by multiplying Vant Hoff Factor with the normal collagative property.
- Since Vant Hoff factor is always less than 1, the abnormal collagative property is always less than normal collagative property.
- Hence, option (3) is incorrect.