(Unless otherwise noted, 2 pts, for cach blank) Molarity of HCT (M) (Opt. each):
ID: 1027536 • Letter: #
Question
(Unless otherwise noted, 2 pts, for cach blank) Molarity of HCT (M) (Opt. each): Volume of HC1 (mL): Mass of Mg (gram) Volume of gas befors placing in Equalization Chamber (ml)a p) Volume of gas after placing Data, Trial 2 Data, Trial 1 0035 4I.S in Equalization Chamber (mL) Barometric Pressure (mm Hg): Temperature (C) Write the balanced overall equation for the reaction of magnesium 31.4 319 and HCl to form hydrogen gas and the magnesium salt (2 pts) Mole of Mg reacted Mole of H: formed (hased on the stoichiometric equation for the reaction) Vapor Pressure of water from curve in mm: 12 Pressure of H: from Dalton's Law in mm Pressure of H: in atm Volume of H: in liter Temperature in Kelvin Calculation of R (6 pts. each) Percent error Average R Calculations (Show al work for trial one.Une the back ir yee seed merespacempeu The calculation for R depends on the assumption that Mg is the limiting reagent. Show the calculations that demonstrate this for Trial 1 . Also besne.explainw how your calculations prove the limiting reagent. (6 ptsbExplanation / Answer
Trial 1:
Moles of Mg reacted = Mass of Mg/ molar mass of Mg = 0.035 g/ 24.305 g/mol = 1.44 X 10-3 moles
From the reaction:
Mg (s) + 2HCl(aq) ----------------> MgCl2 (aq) + H2(g)
Moles of Mg = moles of H2(g)
moles of H2(g), n = 1.44 X 10-3 moles
pressure of H2 = atmospheric pressure - vapor pressure of water at 22 deg
pressure of H2 in mm Hg = 731.90 mm Hg - 19.8 mm Hg = 712.1 mm Hg
pressure of H2 in atm (p) = 712.1/760 atm = 0.937 atm
volume of H2 in L (v) = (40.4 -40.3) X 10-3 L = 0.1 X 10-3 L
Temperature (in K) = 22 deg c = 22+278.15 = 300.15K
R = PV/nT = (0.937 atm * 0.1 X 10-3 L)/(1.44 X 10-3 mol * 300.15 K) = 0.000217 L.atm/mol.K
Actual value of R = 0.08205 L.atm/mol.K
% error = (0.08205 - 0.000217)/0.08205 * 100% = 99.7 %
Trial 2:
Moles of Mg reacted = Mass of Mg/ molar mass of Mg = 0.035 g/ 24.305 g/mol = 1.44 X 10-3 moles
From the reaction:
Mg (s) + 2HCl(aq) ----------------> MgCl2 (aq) + H2(g)
Moles of Mg = moles of H2(g)
moles of H2(g), n = 1.44 X 10-3 moles
pressure of H2 = atmospheric pressure - vapor pressure of water at 22 deg
pressure of H2 in mm Hg = 731.90 mm Hg - 19.8 mm Hg = 712.1 mm Hg
pressure of H2 in atm (p) = 712.1/760 atm = 0.937 atm
volume of H2 in L (v) = (41.9 - 41.5) X 10-3 L = 0.4 X 10-3 L
Temperature (in K) = 22 deg c = 22+278.5 = 100.15K
R = PV/nT = (0.937 atm * 0.4 X 10-3 L)/(1.48 X 10-3 mol * 300.15 K) = 0.000844 L.atm/mol.K
Actual value of R = 0.08205 L.atm/mol.K
% error = (0.08205 - 0.000844)/0.08205 * 100% = 98.9 %
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