LAB 7 DETERMINATION OF THE MOLAR VOLUME OF A GAS AND THE GAS CONSTANT. R PRE-LAB
ID: 1037248 • Letter: L
Question
LAB 7 DETERMINATION OF THE MOLAR VOLUME OF A GAS AND THE GAS CONSTANT. R PRE-LAB QUESTIONS 1. A student did the experiment described except she used Al foil instead of Mg. Her data table included the following values. 0.0352 g 19.08 C Mass of Al Temperature Barometric pressure Volume of H, gas Answer the following questions based on this data table. 762.5 mm Hg 46.92 mL a. Write the balanced equation for the reaction between Aluminum and hydrochloric acid. b. How many moles of Al were consumed? c. How many moles of H, were produced? d. What was the vapor pressure of the water in the gas sample?Explanation / Answer
(a) Balanced equation is
2 Al + 6 HCl --> 2 AlCl3 + 3 H2
2 mol 6 mol 2 mol 3 mol
(c) Given
Volume of H2 gas = 46.92 ml = 0.04692 L
Barometric pressure P = 762.5 mmHg = 762.5 mmHg / 760 = 1.003 atm
Temperature T = 19.08 C = 292.08 K
R = 0.08206 L.atm/mol.K
PV = nRT
1.003 atm * 0.04692 L = n * 0.08206 L.atm/mol.K * 292.08 K
n = 1.964 * 10-3 mol of H2 Answer (c)
(b) according to reaction stoichiometry
2 moles of Al will be consumed when 3 moles of H2 is produced
No. of moles Al = 1.964 * 10-3 mol * 2 / 3 = 1.31 * 10-3 mol
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.