A 0.8250 g of soda ash sample was dissolved in distilled H₂O and diluted to 250-mL using a volumetric flask. This solution was labeled as dilute soda ash solution (DSAS). a. A 50.00 mL aliquot portion of the dilute soda ash solution needed 5.20 mL of 0.1200 M HCI to reach the phenolphthalein end point. About 2-3 drops of methyl orange to the same mixture and it needed 10.00 mL of 0.1200 M HCI to reach the methyl orange end point. 1. Calculate the number of millimoles of HCI needed to reach the phenolphthalein end point. 2. Calculate the number of millimoles of HCI needed to reach the methyl orange end point. 3. What is the %Na₂CO, and %NaHCO, present in the soda ash sample? b. From the dilute soda ash solution (DSAS) two 50-mL portions were obtained. The first portion needed 5.20 mL of 0.1200 M HCI to reach the phenolphthalein end point. The second 50-ml portion needed 15.20 mL to reach the methyl orange end point. 4. Calculate the number of millimoles of HCI needed to reach the phenolphthalein end point and relate the value to the number of mmoles of the basic components present. 5. Calculate the number of millimoles of HCI needed to reach the methyl orange end point and relate the value to the number of mmoles of the basic components present. 6. What is the %Na-CO, and %NaHCO, present in the soda ash sample?

6. In an experiment, the molecular formula for calcium hydroxide was determined to be Ca(OH)2. In this experiment, 0.050 g of Ca (s) was added to 150. mL of DI water. After adding 10 drops of 0.1% thymol blue indicator, the solution was titrated with 0.30 M HCl. a. Write the balanced equation for the net ionic reaction that occurred during the titration. b. Calculate the volume of 0.30 M HCl required to reach the end point of the titration. C. If the initial reading of HCl in the burette was 25.60 mL, what was the final reading of HCl in the burette at the end point of the titration?

15. How much calcium chloride would you dissolve in 250 mL to make 120 ppm primary standard solution of Ca2+ ion? (molar mass of Ca is 40 g/mol and the molar mass of CaCl2 is 111 g/mol) a. 83.3 mg b. 20.6 mg C. 15.0 mg d. 17.6 mg

Acetic Acid Titration with NaOH. 50.00 ml of an acetic acid solution is titrated with 0.1000 M NaOH. 23.90 mL NaOH is required to reach the endpoint of the titration. What is the molarity of the acetic acid solution? (Do NOT include units)

160 140 1. Based on the graph, overall, what happens to the solubility of 120 NaCIo, solid solutes when temperature increases? 100 2. At 10 which solute has the highest solubility? 3. At 10 which solute has the lowest solubility? 4. According to the graph, which substance maintains almost KBr K,Cro. ka constant solubility over the given temperature range? KOO, KM0, 10 20 0 40 so 0 70 s0 KOO. 100 Temperature in degrees C Solubility in grams of anhydrous solute/100gof water "ON'HN

A 1.219-g containing (NH4)2SO4, NH4NO3, and nonreactive substances was diluted to 200 mL in a volumetric flask. A 50.00-mL aliquot was made basic with strong alkali, and the liberated NH3 was distilled into 30.00-mL of 0.08421 M HCl. The excess HCl required 10.17 mL of 0.08802 M NaOH. A 25-mL aliquot of the sample was made alkaline after the addition of Devarda’s alloy, and the NO3- was reduced to NH3. The NH3 from both the NH4+ and NO3- was then distilled into 30.00 mL of the standard acid and back titrated with 14.16 mL of base. Calculate the percentage of (NH4)2SO4 and NH4NO3 in the sample.

A student found that his titration had taken 10 ml of .1002 M NaOH to titrate .132 g of aspirin. Calculate his percent purity. Give a possible explanation of what might have affected his percent purity.

How can you aid in the dissolution of the potassium hydroxide (KOH)? Gentle heating on the hot plate Placing the beaker in an ice bath Stirring the solution Restarting with new pellets

50 ml of .2M KNO3 from 4.0 M stock solution

A 17.5 mL sample of an acetic acid (CH3CO2H) solution required 29.6 mL of 0.250 M NaOH for neutralization. The concentration of acetic acid was __________ M.