While spaying is traditionally recommended for kitties between 4 and 6 months of age, spaying as young as 8 weeks old is considered safe, according to Cat Channel.
The national drinking water standards state that the maximum residual amount of chlorine is 4 mg/L. Untill recently the USA used chlorine gas extensively for wastewater treatment. Today, the use of chlorine has been forced back.
Chlorine molecule. Not necessarily. It depends on the amount of rain and also your current water chemistry. If you have a light rainfall (.25 to .50 inches) of rain, it may temporarily lower the pH in the pool, but not by much and will come back up on it's own. If you always maintain proper water chemistry, especially pH, Alkalinity and Stabilizer, A bit of rain in the pool is nothing to worry about.