you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed into an Erlenmeyer flask with10 ml of water and 2-3 drops of phenolphthalein. It took 32.34ml of NaOH to reach the endpoint. What is the molecular weight and the pKa of the unknown acid?
NaOH + HA ----------> NaA + H2O
moles of NaOH consumed = 0.0925 x 32.34 / 10000 = 0.0030
0.0030 moles acid consumed
moles = mass / molar mass
molar mass= mass / moles = 0.6201 / 0.0030
molar mass = 206.7 g.mol
you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed...
you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed into an Erlenmeyer flask with10 ml of water and 2-3 drops of phenolphthalein. It took 32.34ml of NaOH to reach the endpoint. What is the pKa of the unknown acid? pH at endpoint is 7.19.
Question 2 (10 points) If 25.0 mL of 0.451 M NaOH solution is titrated with 0.253 MH2SO4, the flask at the endpoint will contain (besides the indicator phenolphthalein) as the principal components: sodium hydroxide, sulfuric acid, and water dissolved sodium sulfate and water sodium hydroxide, sodium sulfate, and water dissolved sodium sulfate, sulfuric acid, and water precipitated sodium sulfate and water Question 3 (10 points) A 75.0-ml sample of 0.0650 MHCN (K-62 10-10) is titrated with 0.65 M NaOH. What...
An unknown acid salt was dissolved in water and titrated with 0.105 M NaOH. If 1.20 grams of the salt were dissolved and it took 120 mL to reach the equivalence point, what is the unknown? ( )NaF ( ) NH4Cl ( ) (CH3)3NHCl ( ) NaHCO3
A sample of KHP weighing 0.503 grams was placed in an Erlenmeyer flask and 100 m distilled water was added to dissolve the acid. Two drops phenolphthalein were added and a light pink endpoint was observed after the addition of 27.3 ml NaOH. What is the Molarity of the NaOH solution? Select one: O a. 0.09 M O b. 0.06 M O C. 0.07 M O d. 0.02 M
Standardization of NaOH solution experiment: A 0.75 g sample of pure acid KHP was titrated to phenolphthalein endpoint using 45.34 ml NaOH of unknown concentration. The formula weight of pure KHP is 204.22g/mol. Write the chemical equation for the neutralization reaction, indicate the color change of the indicator at the endpoint, and calculate molarity of the NaOH solution. Show your work. 1. Chemical equation ------------- 2. Endpoint color change ---- 3. NaOH molarity --------- Determine percent purity of impure KHP...
A sample of 0.2140 g of an unknown monoprotic acid was dissolved in 25.0 mL of water and titrated with 0.0950 M NaOH. The titration required 30.0 mL of base to reach the equivalence point, at which point the pH was 8.68. a) What is the molecular weight of the acid? b) What is the pKa of the acid?
An unknown acid is titrated with 0.1 M NaOH following a reaction. Calculate the Molecular Weight and identify what the compound could possibly be if the amount of titrant used was 5.2 mL and the amount of unknown acid is 1.632 grams. (I believe the compound is benzoic acid or close to it; I am mainly looking for the molecular weight).
A vinegar (acetic acid) solution of unknown concentration was titrated to the light pink endpoint with the standardized NaOH solution. The weight volume % of the vinegar solution were calculated. Molecular formula of Acetic acid: C2H4O2 Volume of vinegar sample titrated (ml) 5.00 Volume of NaOH required to neutralize vinegar in (mL) 8.74 Concentration of NaOH in mol/L, 0.1979 Calculate the weight/volume percentage of the vinegar solution (g/100 ml).
A 23.72 ml volume of an H 2A acid solution of unknown concentration with 2 drops of phenolphthalein required 13.58 ml of 0.133 M NaOH to reach the endpoint. What is the molar concentration of the acid solution?
50.00 mL of unknown calcium hydroxide solution is titrated with 0.300 M standard nitric acid solution. If 42.21 mL of the standard acid so lution is required to reach a phenolphthalein endpoint, what is the molarity of the unknown calcium hydroxide solution? (Hint: write the balanced formula unit equation.)