Respuesta :
Answer : The pH of the solution is, 2.06
Explanation : Given,
Mass of HBr = 156 mg = 0.156 g (1 mg = 0.001 g)
Volume of solution = 220 mL
Molar mass of HBr = 80.9 g/mol
First we have to calculate the molarity or concentration of HBr.
Molarity : It is defined as the number of moles of solute present in one liter of volume of solution.
Formula used :
[tex]\text{Molarity}=\frac{\text{Mass of }HBr\times 1000}{\text{Molar mass of }HBr\times \text{Volume of solution (in mL)}}[/tex]
Now put all the given values in this formula, we get:
[tex]\text{Molarity}=\frac{0.156g\times 1000}{80.9g/mole\times 220mL}=0.00876mole/L=0.00876M[/tex]
As 1 mole of HBr dissociates to give 1 mole of hydrogen ion and 1 mole of bromide ion.
So, 0.00876 M of HBr dissociates to give 0.00876 M of hydrogen ion and 0.00876 M of bromide ion.
Now we have to calculate the pH of the solution.
[tex]pH=-\log [H^+][/tex]
[tex]pH=-\log (0.00876)[/tex]
[tex]pH=2.06[/tex]
Thus, the pH of the solution is, 2.06
