For the analysis of unknown soda and vinegar samples, 25.0 mL soda and 1.0 mL vinegar samples were diluted to 50.0 mL in separate Erlenmeyer flasks. KHP, 0.85 g, (Purity = 99.98%; Molar mass = 204.22 g/mol) was titrated with 11.5 mL of NaOH. After the standardization step, it required 0.0143 L of NaOH to reach the endpoint with the soda sample while it took 0.00885 L with the vinegar sample. Phenolphthalein was used as the indicator for the experiment. Express all answers in 2 significant figures. a. Determine the concentration of the titrant (NaOH) b. Determine the concentration of the unknown vinegar sample. c. Determine the concentration of the unknown soda sample.

A chemistry student must write down in her lab notebook the concentration of a solution of sodium thiosulfate. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: • The label on the graduated cylinder says: empty weight: 6.0 g • She put some solid sodium thiosulfate into the graduated cylinder and weighed it. With the sodium thiosulfate added, the cylinder weighed 94.86 g. • She added water to the graduated cylinder and dissolved the sodium thiosulfate completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 122.28 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. 1 [1] 8.mL-¹ x10 X Ś

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A chemistry student is given 1.00 L of a clear aqueous solution at 17 degrees Celsius. He is told an unknown amount of a certain compound X is dissolved in the solution. The student allows the solution to cool to 17 degrees Celsius. The solution remains clear. He then evaporates all of the water under vacuum. A precipitate remains. The student washes, dries and weighs the precipitate. It weighs 0.12 kg. Using only the information above, can you calculate the solubility of X in water at 17° C? If you said yes, calculate it and be sure your answer has a unit symbol and 2 significant digits.

4) Write a chemical equation describing the dissolution of Ba(NO3)2 in water. To give you an example of what I'm looking for, for NaBr, the equation would be NaBr(s) → Na*(aq) + Br- (aq). 5) Based on your equation from question 4, if 41.9 g of Ba(NO3)2 are dissolved in water to produce a total solution volume of 495 mL, determine the molarity of NO3- in the solution?

A 0.1675-g sample of pure Na2C2O4 (134.00 g/mol) was titrated with 49.75 mL of KMnO4. What is the normality of the KMnO4 solution? The chemical reaction is                  2MnO4 - + 5C2O4 2- + 16H+ → 2Mn2-  +  10CO2 + 8H2O

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A TUMS tablet was dissolved in 110.00 mL of 0.1022 M HCl and analyzed for CaCO3 according to the procedure described in the lab manual. It took 7.48 mL of 0.1005 M NaOH to reach the endpoint. Calculate the mass of CaCO3 in the TUMS tablet to the correct number of significant figures.

A buret is used to measure the volume of FeCl3 aqueous solution. The starting volume is recorded to be 5.28 mL. The ending volume is recorded as 17.44 mL. What is the total volume of FeCl3 solution dispensed?

Suppose 0.324 g of copper(II) acetate is dissolved in 100. mL of a 0.20 M aqueous solution of sodium chromate. Calculate the final molarity of copper(II) cation in the solution. You can assume the volume of the solution doesn't change when the copper(II) acetate is dissolved in it. Be sure your answer has the correct number of significant digits. Ом x10 X 3