determining the molar volume of a gas experiment 8

• High School
• You don't have any recent items yet.
• You don't have any courses yet.
• You don't have any books yet.
• You don't have any Studylists yet.
• Information

Molar Volume of a Gas Lab

General chemistry (202-nya-05), dawson college, recommended for you, students also viewed.

• Stoichiometry Experiment Lab
• Atomic Emission Spectra Lab
• Lab #7 - Atomic Emission Spectra - Google Docs
• Lab Atomic Emission Spectra
• Lab Molar Volume of a Gas
• Atomic Spectra Lab #7 - lab report

Related documents

• Identification Of Anions And Cations Lab #6
• Chemical reactions lab #5
• Solution Stoichiometry Lab #2
• Volumetric analysis of Cu2+ lab4
• Atomic Emission Spectra Lab - general chemistry
• Volumetric analysis lab report

Related Studylists

Preview text.

Molar Volume of a Gas: Experiment # Macey Zemel 1939367 Partner: Emma Rothstein

202-NYA-05, GENERAL CHEMISTRY, Section 00016, Jubrail Rahil

Tuesday, October 8, 2019

Introduction

-Objectives:

The objectives of this experiment are to determine the molar volume of H 2 gas produced by the reaction: Mg (s) + 2 HCl (aq)  H 2 (g)+ MgCl 2 (aq), as well as calculate the molar volume of H 2 gas at STP.

According to Avogadro, equal volumes of all gases at the same temperature contain the same number of particles regardless of the identity of the gas. His hypothesis states as well that at constant temperature and pressure, the volume of any gas is directly proportional to the number of moles of any gas.

The molar volume is the volume occupied by one mole. The molar volume is defined by following formula: (V= molar volume, v =volume, n= moles)

The molar volume is being compared it to an ideal gas at standard conditions (0°C, 101 kPa). Molar volume is calculated through the following formula where V is molar volume, R is universal gas constant, T is temperature (K) and P is pressure (kPa). RT/P

Dalton’s law of partial pressures is used to determine the partial pressure of hydrogen gas and the large graduated cylinder. The pressure punching gases collected as measured through water displacement. The formula for the partial pressure of hydrogen gas is the following:

P= P H 2 + P H 2 O

P total = P H 2 + P H 2 O P H 2 = P total - P H 2 O = 102 KPa – 2 KPa = 100 KPa

The Molar volume of H 2 and STP P1V1 / T 1 = P2V2 /T (100 KPa)(25 L) / (21°C + 273) = (101 KPa)(V)/ 273 V= 23 L/mol

Percent Error (Theoretical – Experimental / Theoretical) x 100 [(22 L/mol - 23 L/mol) / 22 L/mol ] x 100 = 4 %

Discussion/conclusions

After completing the experiment, as well as doing the calculations, the results obtained for the molar volume of hydrogen gas at STP was 23 L/mol. Therefore, the percent error calculated was 4% as the molar volume at STP is supposed to be 22 L/mol. This percent error is caused by sources of errors that occurred throughout the lab. Firstly, there may have been systematic sources of error, meaning that there were some inaccuracies of the measuring tools, such as the thermometer, the barometer, the beaker, the balance and the graduated cylinder. Secondly, it is possible that the conditions of pressure and temperature at Dawson/of the room changed causing for the percent error to increase. Overall, the objective was met as the goal of this experiment was to determine the molar volume of hydrogen gas at standard conditions. Even though there was the percent error of 4%, the objective was still completed.

Reference General Chemistry Laboratory Experiments 202-NYA-05 (Revised Fall 2017). Dawson College.

Post Laboratory Questions:

• Assuming that the mass of magnesium is kept constant, what happens to the actual yield of the reaction if the molarity of the hydrochloric acid used is reduced when:

a) The hydrochloric acid remains in excess

The actual yield of the reaction will stay the same because HCl is not the limiting reagent, therefore, the values used in calculations will only acknowledge the mass of hydrochloric acid that is being reacted with, not its excess.

b) The hydrochloric acid is the limiting reagent

If the hydrochloric acid is the limiting reagent, the actual yield will change. It will decrease since the moles of hydrogen gas will decrease because not all of the magnesium was able to react. This will therefore decrease the final molar volume and result in a lower yield.

• Explain how Avogadro’s hypothesis relates to the result obtained in this experiment

Avogadro’s hypothesis states that at constant temperature and pressure, the volume of any gas is directly proportional to the number of moles of any gas. Therefore, the molar volume of the hydrogen gas at 237K and 1 atm should be equal to 22 L/mol.

(101 kPa)(V) = (1 mol)(8 kPaL/molK)(300K) v= 24 L/mol

• In the reaction between HCl and Mg ribbon, 40 ml of a gas mixture, collected in a gas collection tube at constant T and P, contained H 2 gas that was mixed with gaseous H 2 O. If 35 mL of the gas mixture contained 1 x 10- mole of H 2

a) What mass of H 2 O was present in the gas mixture you collected? 40 mL – 35 mL = 5 mL H 2 O =0 L n1/v1 = n2/v 0 mol / 0 L = n2 / 0 n2 = 0 (0 x 18 g/mol) = 0 g

b) What is the mole % of H 2 O in the mixture? [ 0 / (0 mol + 0) ] x 100 = 12 %

• Multiple Choice

Course : General Chemistry (202-NYA-05)

University : dawson college.

• Discover more from: General Chemistry 202-NYA-05 Dawson College 403   Documents Go to course
• More from: General Chemistry 202-NYA-05 Dawson College 403   Documents Go to course
• More from: Chem by Giulia Balleine 14 14 documents Go to Studylist