1. As I understand it--As an acid is added to neutral water the (OH-) will...decrease?? Is this right?
2. If you made up a solution of NaOH by adding 0.010 mole of solid NaOH to 1.0 L of distilled water, what would be the concentration of the OH-?...I think this would be a pOH of 2, then I calculated the OH- to be 10^-2 which= .01.....Is this correct??
3. One mole of the acid HCL requires how many moles of OH- for neutralization? I think it is 1 mole...Is this correct? :)
4. A solution has a pH of 2.5. What is the (H+)?...I calculated it to be .00316 or 3.6 x 10^3? Is this right?
Thank-YOU so much!!!
Yes, yes, yes, yes.
However, you made a lot of extra work of 2.
If NaOH is 0.01 mol in 1 L, then OH^- is 0.01 M. You don't need to go through pOH and back to OH.
1. Yes, you are correct. When an acid is added to neutral water, the concentration of hydroxide ions (OH-) will decrease. This is because the acid donates protons (H+) to the water, resulting in an increase in the concentration of hydronium ions (H3O+), while the concentration of hydroxide ions decreases. Thus, the solution becomes more acidic.
2. To find the concentration of hydroxide ions (OH-) in the NaOH solution, you need to consider the dissociation of NaOH in water. NaOH dissociates completely into Na+ and OH- ions. Since you added 0.010 mole of NaOH to 1.0 L of water, the concentration of hydroxide ions can be calculated as follows:
Concentration of OH- = moles of OH- / volume of solution
Concentration of OH- = 0.010 mole / 1.0 L
Concentration of OH- = 0.010 M
So, your calculation is incorrect. The concentration of OH- is 0.010 M, not 0.01.
3. You are correct again. In a neutralization reaction between HCl and a base, such as NaOH, the stoichiometry is 1:1. It means that one mole of HCl requires one mole of OH- ions for neutralization.
4. The formula for pH is given by pH = -log10([H+]), where [H+] represents the concentration of hydrogen ions (H+). In this case, you are given a pH value of 2.5.
[H+] = 10^(-pH)
[H+] = 10^(-2.5)
[H+] = 0.00316 M
So, your calculation is correct. The concentration of hydrogen ions (H+) is 0.00316 M or 3.16 x 10^(-3) M.