I want to make solutions of pH 3.5, 4.5, 6.5, 8.5 and 10.5 from 0.1 M HCl and 0.1 M NaOH. how many ml shall I take from each solution to make these pH levels?
To determine the volumes of 0.1 M HCl and 0.1 M NaOH required to make solutions with specific pH levels, you'll need to consider the dissociation of these acids and bases in water.
For the provided pH values, we can assume that the solutions will have equal concentrations of acid (HCl) and base (NaOH). Therefore, the concentration of H+ ions (acidic) and OH- ions (basic) will be equal.
To calculate the volumes, we can use the formula:
[H+] = 10^(-pH)
Where [H+] represents the concentration of H+ ions.
Step 1: Calculate the concentrations of H+ (acid) and OH- (base) ions:
[H+] = 10^(-pH)
[H+] = 10^(-3.5) for pH 3.5
[H+] = 10^(-4.5) for pH 4.5
[H+] = 10^(-6.5) for pH 6.5
[H+] = 10^(-8.5) for pH 8.5
[H+] = 10^(-10.5) for pH 10.5
Since the acid (HCl) and base (NaOH) have equal concentrations, the concentration of OH- ions will be the same as H+ ions.
Step 2: Calculate the volumes:
[H+] = [HCl] = [NaOH]
[OH-] = [NaOH] = [HCl]
[HCl] * [OH-] = 10^(-pH)
Using the concentrations of H+ and OH- ions, we can substitute [HCl] and [NaOH] in the above equation:
0.1 * 0.1 = 10^(-pH)
Now, solve for the volumes (V):
V = 0.01 / 10^(-pH) = 0.01 * 10^(pH)
Calculate the volumes required for each pH level:
V(pH 3.5) = 0.01 * 10^(3.5)
V(pH 4.5) = 0.01 * 10^(4.5)
V(pH 6.5) = 0.01 * 10^(6.5)
V(pH 8.5) = 0.01 * 10^(8.5)
V(pH 10.5) = 0.01 * 10^(10.5)
Evaluate the volumes to obtain the answer.