Answer to Question #71508 in Physical Chemistry for rohan

Question

Prove that change in ionic cloud is equel and apposit to centrel ion in which is responsible for its formation

Answer 1

Around each positive ion in the solution can be any ions - both positive and negative. But the probability of finding negative ions will be greater. Around the negative ions are any ions - both positive and negative, but always near negative ions the probability of finding positive ions will be greater. As a result, on average, the excess amount of positive electricity around these negative ions is equal to the charge of these ions.
Hence, Debye and Hückel moved on to the concept of the so-called ionic atmosphere. They suggested that around each central ion (any ion can be chosen as the central ion), an ion cloud consisting of positive and negative charges with an excess of (negative or positive) charges is formed, so that, however, the whole solution remains neutral.
Consider a positive ion as the central one. Around this ion can be any distribution of positive and negative ions. At a separate point in time, there may even be an excess of positive ions over negative ions. But if you follow the system for a sufficient amount of time, it turns out that on average there is some excess of negative charges over positive ones. This excess is equal to the positive charge of the central ion. In this case, the negative charge is distributed over the entire shell surrounding the ion. Thus, around the positive ion a negatively charged atmosphere is formed.