Which of the following buffer solution turns invalid on addition of 10 mL of 1.0 M HCl ?

Question

Which of the following buffer solution turns invalid on addition of 10 mL of 1.0 M HCl ? (A) 100 mL having 0.15 M NH3 and NH4Cl each (B)  100 mL having 0.2M NH3 and NH4Cl each (C)  100 mL having 0.2M NH3 and 0.1 M NH4Cl each (D)  100 mL having 0.05 M NH3 and NH4Cl each

Tardigrade Admin · Accepted Answer

Millimoles of NH 3=100 × 0.05=5 m mol Added HCl =10 × 1.0 M =10 m mol NH 3 gets completely neutralised, solution turns acidic that is now not the buffer solution. In all other cases, m moles of NH 3 are higher as compared to m moles of HCl. Thus, they remain as buffer.

Q. Which of the following buffer solution turns invalid on addition of $10 m L$ of $1.0 M H Cl$ ?

$100 m L$ having $0.15 M N H_{3}$ and $N H_{4} Cl$ each

$100 m L$ having $0.2 M N H_{3}$ and $N H_{4} Cl$ each

$100 m L$ having $0.2 M N H_{3}$ and $0.1 M N H_{4} Cl$ each

$100 m L$ having $0.05 M N H_{3}$ and $N H_{4} Cl$ each

Q. Which of the following buffer solution turns invalid on addition of 10mL of 1.0MHCl ?

100mL having 0.15MNH3​ and NH4​Cl each

100mL having 0.2MNH3​ and NH4​Cl each

100mL having 0.2MNH3​ and 0.1MNH4​Cl each

100mL having 0.05MNH3​ and NH4​Cl each

Millimoles of NH3​=100×0.05=5mmol Added HCl=10×1.0M=10mmol NH3​ gets completely neutralised, solution turns acidic that is now not the buffer solution. In all other cases, m moles of NH3​ are higher as compared to m moles of HCl. Thus, they remain as buffer.

Q. Which of the following buffer solution turns invalid on addition of $10 m L$ of $1.0 M H Cl$ ?

$100 m L$ having $0.15 M N H_{3}$ and $N H_{4} Cl$ each

$100 m L$ having $0.2 M N H_{3}$ and $N H_{4} Cl$ each

$100 m L$ having $0.2 M N H_{3}$ and $0.1 M N H_{4} Cl$ each

$100 m L$ having $0.05 M N H_{3}$ and $N H_{4} Cl$ each