If you made up a solution of NaOH by adding 0.010 mole of solid NaOH to 1.0 liter of distilled water, what would be the pH of the solution?
pH = -log[H+]
pOH = -log[OH-]
and pH = pOH = 14
pOH = -log(0.01) = 2
2 + pH = 14; pH = 12
pH = the negative of the exponent of concentration
pH = the H+ concentration
To find the pH of a solution of NaOH, we need to consider the concentration of hydroxide ions (OH-) in the solution. When NaOH dissolves in water, it completely dissociates into Na+ and OH- ions.
Given that you added 0.010 mole of solid NaOH to 1.0 liter of water, we can calculate the concentration of OH- ions.
Concentration (in moles per liter) = number of moles / volume (in liters)
Concentration of OH- ions = 0.010 mole / 1.0 liter = 0.010 M
Since the concentration of OH- ions is known, we can use the relationship between OH- and H+ ions to find the pH.
In a neutral solution, the concentration of H+ ions is equal to the concentration of OH- ions. Since NaOH is a strong base, it completely dissociates to form 0.010 M OH- ions. Therefore, the concentration of H+ ions will be equal to 0.010 M as well.
pOH = -log10 [OH-]
pOH = -log10 (0.010)
pOH = 2
The pH scale is defined as pH + pOH = 14. Therefore, we can find the pH using the pOH value:
pH = 14 - pOH
pH = 14 - 2
pH = 12
Therefore, the pH of the solution made by adding 0.010 mole of solid NaOH to 1.0 liter of distilled water is 12.
To determine the pH of a solution of NaOH, you need to consider that NaOH is a strong base that completely dissociates in water. This means that it breaks apart into ions: Na+ (sodium cation) and OH- (hydroxide anion).
Since NaOH is a strong base, it completely reacts with water to produce OH- ions. The concentration of OH- ions can be calculated by dividing the moles of NaOH by the volume of the solution.
In this case, you have added 0.010 mole of NaOH to 1.0 liter of water. Therefore, the molar concentration of OH- ions in the solution is 0.010 M.
The pH of a solution can be determined using the equation: pH = -log[H+].
Since OH- ions are the conjugate base of water, they react with H+ ions to form water. The concentration of H+ ions in pure water is 1.0 x 10^-7 M. However, in a solution of NaOH, the concentration of H+ ions is negligible compared to the concentration of OH- ions. Therefore, we can assume that the concentration of H+ ions is 0 for this calculation.
Taking the negative logarithm of 0 gives us an undefined value (-log(0) = Undefined). So, the pH of the NaOH solution is undefined.
In this case, instead of calculating the pH, we can determine the pOH (the negative logarithm of the concentration of OH- ions). The pOH can be calculated using the equation: pOH = -log[OH-].
The pOH of the solution is -log(0.010) = 2.
To find the pH, we can use the relationship between pH and pOH: pH + pOH = 14 (in an aqueous solution at 25°C).
Therefore, the pH of the NaOH solution is 14 - pOH = 14 - 2 = 12.