{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Determining Unknown Gases

# Determining Unknown Gases - Determining Unknown Gases...

This preview shows pages 1–3. Sign up to view the full content.

Determining Unknown Gases Archelle Grajeda, TA Steven Melhorn, Professor Neshyba CHEM 110 EB, December 5, 2007 INTRODUCTION Pressure, volume, temperature, and the amount of moles constitute the three main gas laws. The three gas laws by Charles, Boyles, and Avogadro each explain the relationship between volume and temperature, volume and pressure, and the volume and amount of moles respectively. The three laws make up an “all-encompassing” relationship between the four variables called the Ideal Gas Law 1 . In this lab, the Ideal Gas Law, PV=nRT, becomes a familiar and useful tool in order to determine unknown gases. This lab illustrates how the Ideal Gas Law can be used in order to find the molar mass of an unknown gas. It is a useful law that allows scientists in real life situations to determine what a certain gas could actually be. This could be useful to detect potentially harmful or toxic gases in real life situations. EXPERIMENTAL General Three 250ml Erlenmeyer were filled by three unknown gases provided by the Chemistry department. A balance was used to measure the mass of the unknown sample. A Bunsen burner was used to aid the flame test. The experiment was performed at room temperature and an atmospheric pressure. Procedure First, three 250ml empty flasks (only filled with air) were measured using a balance. Then the grams of air in the flask were calculated by using the Ideal Gas Law PV=nRT.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
In order to find the mass of only the flask and stopper without the air, the grams of air calculated were subtracted from the measured grams of the empty flask. The atmospheric pressure of the room was determined from a barometer in the lab and the temperature was obtained from a thermometer. Finding Molar Mass The mass of air measured in a 250ml Erlenmeyer flask was 0.3024g. The mass of air was subtracted from the mass obtained from the flask. Each three flasks were filled then with an unknown gas. The mass of all flasks were measured using the same balance. The mass of the unknown sample was calculated by subtracting 0.3024 from the mass of the flasks filled with unknown gases. The value of an empty flask without air was subtracted from the mass of the flask filled with unknown gas to obtain only the grams of unknown gas.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}