A scale shows colors from red to purple with labels from the red end of 0, 1 gastric acid, 2 lemon juice, 3 orange juice, 4 tomato juice, 5 black coffee, 6 urine, 7 distilled water, 8 sea water, 9 baking soda, 10 milk of magnesia, 11 ammonia, 12 soapy water, 13 bleach, 14. Familiar solutions can have a wide range of pH levels. According to the chart, which is the strongest acid, based on its pH level? Lemon juice has approximately how many more times the H+ ions than tomato juice? Which has the highest concentration of H+ ions: baking soda, ammonia, or bleach?