aerialsprite
New Member
- Joined
- Oct 30, 2003
- Messages
- 19
Could someone please help me with either of these two questions?
1) Pthalic acid is a weak diprotic acid for which we can write the formual as H2(C8H4O4). Potassium hydrogen phtalate KH(C8H4)4) is a good primary standard for standardising alkali solutions. It contains one acidic hydrgoen per formual unit. 0.917g potassium hydrogen phtalate was dissolved in water and titrated with approximately 0.2 mol/L sodium hydroxide solution; 27.2 mL hydroxide solution was needed to reach the end point. Calculate the molatrity of the hydroxide solution.
2) 'Cloudy ammonia' is often used in the home as a cleaning agent. To determine the concentration of ammonia in the solution, a chemist first accurately diluted 25mL (by pipette) to 500 mL (volumetric flask) then titrated 25Ml (by pipette) of the dilute solution with 0.151 mol/L nitric acid solution; it required 27.2 mL. Calculate the molarity of the original ammonia solution.
(ref: conquering chem p 155 q17 and 19)
1) Pthalic acid is a weak diprotic acid for which we can write the formual as H2(C8H4O4). Potassium hydrogen phtalate KH(C8H4)4) is a good primary standard for standardising alkali solutions. It contains one acidic hydrgoen per formual unit. 0.917g potassium hydrogen phtalate was dissolved in water and titrated with approximately 0.2 mol/L sodium hydroxide solution; 27.2 mL hydroxide solution was needed to reach the end point. Calculate the molatrity of the hydroxide solution.
2) 'Cloudy ammonia' is often used in the home as a cleaning agent. To determine the concentration of ammonia in the solution, a chemist first accurately diluted 25mL (by pipette) to 500 mL (volumetric flask) then titrated 25Ml (by pipette) of the dilute solution with 0.151 mol/L nitric acid solution; it required 27.2 mL. Calculate the molarity of the original ammonia solution.
(ref: conquering chem p 155 q17 and 19)
