Question

For an ideal solution of two components A and B, which of the following is true?

• A. $\Delta H_{mixing}<0\left(zero\right)$
• B. $\Delta H_{mixing}>0\left(zero\right)$
• C. A - B interaction is stronger than A - A and B - B interactions
• D. A - A, B - B and A - B interactions are identical

Answer 1

The correct option is D A - A, B - B and A - B interactions are identical

The solutions which obey Raoult's law over the entire range of concentration are known as ideal solutions. The ideal solutions have two other important properties. The enthalpy of mixing of the pure components to form the solution is zero and the volume of mixing is also zero.

At a molecular level, ideal behaviour of the solutions can be explained by considering two components A and B. In pure components, the intermolecular attractive interactions will be of types A-A and B-B, whereas in the binary solutions in addition to these two interactions, A-B type of interactions will also be present. If the intermolecular attractive forces between the A-A and B-B are nearly equal to those between A-B, this leads to the formation of the ideal solution.

Hence, as the given solution is ideal, the correct option is $\left(D\right)$.