Question

calculation required for Q. 2: Calculation of mass of CaCO3 sample for analysis.

solid calcium carbhotae samples, calcium bicarbonate, CalHCO), i abo prscn. 1. In some calciunm for its reaction with hydrochloric acid. (og) 2 Experimental Procedure, Part A.2a. Complete the calculation required to appear on the Report Sheet (here and Report Sheet). 3. a. Experimental Procedure, Part A.3b. Explain how a water-filled graduated cylinder is inverted in a pan of water. b. Experimental Procedure, Part A.4. What is the proper procedure for inserting a piece of glass tubing into a ru stopper? 4. Experimental Procedure, Part C.1. How is the volume of the CO(8) collected (over water) measured in this experiment? the space (or volume) in which the CO-(g) is collected in this experiment. 5. A thermometer is not present in a. How then is the temperature of the CO(8) determined in this ex is the mass of the CO,(g) collected over water determined in this experiment? table of Trial 1 (See Report Sheet.) for determining the molar volume of ot Caco, in a heterogeneous micture. See Figure 13.4 and Equation 13.1. ReOs and t Co, and the pe. Record calcue . a Complete th laloning uhle of Thal i Ss ke cent composition of CaCO, in a values with the correct number of significant figures A. Sample Preparation and Setup Apparatius 1, Mass of sample α) 2. Mass of generator + sample before reaction (e) $7.719 Da C. Determination of Volume, Temperature, and Pressure of the Carbon Dioxide Gas 3. Volume of CO(g) collected (L) 4. Temperature of water C'C) 5. Barometric pressure (torr) 6 Vapor pressure of H,0 at 20.0°C 7. Pressure of dry COieXtorr) A. Part D.2 Show calculation D. Amount of Carbon Dioxide Gas Evolved I. Mass of generator + sample after reaction (g) 87.642 2. Mass loss of generator mass of Part D.3 CO, evolved (g) Show calculation 3. Moles of CO,(g) cvolved (mol) Show calculation E. Molar Volume of CO, Gas Part E.2 2. Volume of CO-(g) at STP (L) Equation 134 Show cakculation. 3. Molar volume of COjg) at STP (Lmob Equation 13.2 Show cakculation F. Percent CaCO, in Mixture Part E.3 1. Moles of CaCO, in sample from mol CO, generated (mol) 2. Mass of CacO, in sample (g) Show calculation. 3. Mass of original sample (g) 4. Percent of CaCO, in sample (%) Part F.2 37.7 mL 770 torr 186 A Carbonate Analysis; Molar Volume of Carbon Dioxide

Answer 1

Vapor pressure of water at 20C = 17.5 torr

Pressure of dry carbon dioxide in torr = 770 torr - 17.5 torr = 752.5 torr = 0.99 atm ( 1atm = 760 torr)

Mass loss of generator = Mass of CO₂ evolved = (Mass of generator + sample before reaction) - ((Mass of generator + sample after reaction) = 87.719 g - 87.642 g = 0.077 g

Ideal gas equation /;

PV = nRT

0.99 atm x 0.0377 lt = n x 0.0821 l atm/mol K X 293 K

0.03733 moles /24.0553 = n

n = 0.001552 moles

Molar volume of CO₂ at STP = V/n = 0.0377 lt/0.001552 moles = 24.29 lt/mol

molar mass of CaCO₃ = 100 g/mol

mass of calcium carbonate = moles x molar mass = 0.001552 moles x 100 g/mol = 0.1552 gms

mass of calcium carbonate in original sample = 0.276 g

Percent of calcium carbonate = mass of calcium carbonate calculated/mass of calcium carbonate original = 0.1552 gms/0.276 g) x 100 = 56.23 %