*This blog post is for Monday, April 25th.*
In all four of my group's experiments, we have maintained a constant relationship in which 10 mL of Windex is dissolved into 400 mL of alkaline water, or a 1 : 40 ratio, because that is the average presence of ammonia in Lake Michigan. However, at what concentration does the Windex no longer affect the pH of the water? To test this, on Friday, we added 5 mL at a time to our solution, each time observing the color change of the Universal Indicator. The solution remained a deep blue color, or pH level 8, at a ratio of 10 mL of Windex to 700 mL of alkaline water (1 : 70 ratio). From there, we calculated the molarity of the solution:
Density of Ammonia: 0.83 g/mL
Volume of Ammonia: 10 mL
Mass of Ammonia: 8.3 grams NH3
Molar Mass of Ammonia: 17.04 g/mol NH3
Moles of Ammonia: 0.49 mol NH3
Volume of Solution: 701 mL (0.701 L)
Molarity of Solution: M = n/v
M = 0.49 / 0.701
M = 0.70 M
The value above, 0.70 M, is the concentration in which the basicity of the Windex product no longer changes the pH of Lake Michigan. This means that as consumers, we don't have to eliminate the use of household cleaners altogether. However, we must reduce our consumption to the point in which it won't disrupt normal aquatic environments.
-Gretchen Koomjohn
In all four of my group's experiments, we have maintained a constant relationship in which 10 mL of Windex is dissolved into 400 mL of alkaline water, or a 1 : 40 ratio, because that is the average presence of ammonia in Lake Michigan. However, at what concentration does the Windex no longer affect the pH of the water? To test this, on Friday, we added 5 mL at a time to our solution, each time observing the color change of the Universal Indicator. The solution remained a deep blue color, or pH level 8, at a ratio of 10 mL of Windex to 700 mL of alkaline water (1 : 70 ratio). From there, we calculated the molarity of the solution:
Density of Ammonia: 0.83 g/mL
Volume of Ammonia: 10 mL
Mass of Ammonia: 8.3 grams NH3
Molar Mass of Ammonia: 17.04 g/mol NH3
Moles of Ammonia: 0.49 mol NH3
Volume of Solution: 701 mL (0.701 L)
Molarity of Solution: M = n/v
M = 0.49 / 0.701
M = 0.70 M
The value above, 0.70 M, is the concentration in which the basicity of the Windex product no longer changes the pH of Lake Michigan. This means that as consumers, we don't have to eliminate the use of household cleaners altogether. However, we must reduce our consumption to the point in which it won't disrupt normal aquatic environments.
-Gretchen Koomjohn