Common Liquid pH Value
Battery Acid 0.0
Stomach Acid 1.4
Vinegar 2.9
Soft Drink 3.0
Wine 3.5
Coffee 5.0
Urine 6.0
Blood 7.35-7.45
Tears 7.3-7.5
Seawater 8.0
Soap, Shampoo 8.0-9.0
Milk of Magnesia 10.0
Household Ammonia 11.8

Pool Chemical pH Value
Muriatic Acid 0.1
Gas Chlorine 0.1
Dry Acid 1.4
Trichlor 2.8
Cyanuric Acid 3.0
Bromine Tabs 3.6
Dichlor 6.8
Sodium Bicarb 8.3
Sodium Sesqui 10.1
Lithium Hypo 10.7
Cal Hypo 11.8
Soda Ash 13.0
Liquid Chlorine 13.0

Here are some pH vales of pool chemicals and some common liquids.

The pH value of your pool changes when a sufficient amount and concentration of any chemical enters the water. Most of the time a small amount and concentration will have a little affect on the water's pH. For instance, if you add a gallon of liquid chlorine to the pool, it should not change the pH very much. If it does, you need more total alkalinity.

Total alkalinity is the buffering system in the water. Too little and the pH moves easily up or down. Too little and the pH won't move at all. The proper total alkalinity depends on the sanitizer being used for regular sanitation. Acidic sanitizers like trichlor, bromine tabs and gas chlorine need a TA of 120-140 ppm, alkaline sanitizers like liquid chlorine, cal hypo and lithium hypo need a TA of 80-100 ppm. Dichlor, 2-part bromine and combination of sanitizers need a TA of 100-120 ppm.

Always adjust alkalinity first then adjust pH. And, make sure the calcium hardness is a minimum of 150 ppm and better is between 200-400 ppm.