Respuesta :
Answer: The number of [tex]OH^-[/tex] ions dissociated are [tex]8.57\times 10^{11}[/tex]
Explanation:
We are given:
pH = 2.07
Calculating the value of pOH by using equation, we get:
[tex]2.07+pOH=14\\\\pOH=14-2.07=11.93[/tex]
To calculate hydroxide ion concentration, we use the equation to calculate pOH of the solution, which is:
[tex]pOH=-\log[OH^-][/tex]
We are given:
pOH = 11.93
Putting values in above equation, we get:
[tex]11.93=-\log[OH^-][/tex]
[tex][OH^-]=10^{-11.93}=1.17\times 10^{-12}M[/tex]
To calculate the number of moles for given molarity, we use the equation:
[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}[/tex]
Molarity of solution = [tex]1.17\times 10^{-12}M[/tex]
Volume of solution = 1243 mL = 1.243 L (Conversion factor: 1 L = 1000 mL)
Putting values in above equation, we get:
[tex]1.17\times 10^{-12}M=\frac{\text{Moles of }OH^-}{1.243L}\\\\\text{Moles of }OH^-=(1.17\times 10^{-12}mol/L\times 1.243L)=1.424\times 10^{-12}mol[/tex]
According to mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of particles
So, [tex]1.424\times 10^{-12}mol[/tex] number of [tex]OH^-[/tex] will contain = [tex](1.424\times 10^{-12}\times 6.022\times 10^{23})=8.57\times 10^{11}[/tex] number of ions
Hence, the number of [tex]OH^-[/tex] ions dissociated are [tex]8.57\times 10^{11}[/tex]
