Question

When solid borax is dissolved in water do you expect entropy of the system to increase or decrease?will the sign of delta s be posoitive or negative?

Answer 1

When solid borax is dissolved in water, the entropy of the system increases, and the sign of ΔS is positive due to the greater dispersal of matter as the solid lattice breaks down into ions in solution.

Step-by-step explanation:

Entropy Change when Dissolving Borax in Water

When solid borax is dissolved in water, the entropy of the system is expected to increase. Entropy, which is denoted by ΔS, is a measure of disorder or randomness in a system. The dissolution process typically leads to an increase in disorder as the structured solid lattice breaks down into dispersed, hydrated ions in solution. Consequently, the sign of ΔS will be positive. This is similar to disruption of a crystal lattice when a salt like NaCl dissolves, which outweighs the ordering effect of water molecules forming ordered arrangements around the ions, resulting in a net increase in entropy. Therefore, the dissolution of borax in water leads to increased dispersal of matter and a positive entropy change.

Examples that also show an increase in entropy when a solid dissolves into ions in solution include the dissolution of NaNO3 to form Na+ and NO3- in water, as well as the sublimation of CO₂ from a solid to a gas. Contrarily, the freezing of liquid water represents a decrease in entropy, and the sign of ΔS would be negative in this case, as the state changes from a less ordered liquid to a more ordered solid.

Answer 2

Step-by-step explanation:

As we know that entropy means the degree of randomness present within the molecules of a substance.

Hence, disorderly the atoms of a substance are more will be its entropy. So, when more is the entropy then sign of entropy change is positive. Similarly, less is the entropy then sign of entropy change will be negative.

For example, when solid borax is dissolved in water then its atoms move away from each other. This means that degree of randomness increases with its solubility in water.

Thus, we can conclude that when solid borax is dissolved in water then entropy of the system increases and sign of
`\Delta S` is positive.