The change in the observed boiling point versus the expected boiling point is known to be a result of abnormal molar mass. The scientist van’t Hoff introduced a factor to understand the value of dissociation and association. The van’t Hoff factor “i” is the ratio of normal molar mass to abnormal molar mass. It is the ratio of observed colligative property to calculated colligative property. Hence, the correct options are (i) and (iii) and incorrect options are (ii) and (iv).