Answer: 0.3794 moles of Iodine gas are produced.
Explanation:

Volume of iodine gas produced at STP =8.5 L
At STP, the 1 mol of gas occupies volume = 22.4 L
So, 8.5 L of volume will be occupied by:
0.3794 moles of Iodine gas are produced.
What do you need help with? Can you specify?
Answer:
The signs of chemical change include changes in color, temperature, the production of light, changes in odor, and the formation of gases.
I believe it’s conductivity
There are two reasons that account for the change in concentration. One is by the physical change and second is by the chemical change. The physical change refers to the mixture of the two compounds. The concentration is the amount of that certain substance to the whole mixture. Since the mixture increases because you add them up, the concentration decreases. Second, these compounds react with each other once they interact. Hence, their amounts would be consumed in order to produce the products.