The numbers of Jinmuhuo, Shuitu are 1, 2, 3, 4 and 5. Then 12 is not adjacent, 23 is not adjacent, 34 is not adjacent, 45 is not adjacent, and 15 is not adjacent.

Let event A mean that "two substances with similar properties in the arrangement are not adjacent", then the probability of event A is:

All the permutations are 5*4*3*2.

Let's calculate what will happen in event a:

The first position has five options, which is 5.

Second position: every number has two other numbers that cannot be adjacent, so you can choose two.

Third position: the first position cannot be selected, nor can the two adjacent positions be selected, only 1 can be selected.

In the fourth and fifth positions, there are two numbers that can be changed by line, which are two choices.

So there are 5*2*2 non-adjacent situations.

Finally, the probability of event A is 5*2*2/5*4*3*2= 1/6.