An experiment to demonstrate the concept of molar mass and to introduce the combination of variables

Some are irritants, some haveoffensive odors, and nearly all are flammable. The usefulness of defining concentration by moles per liter or molarity is that it defines the number of molecules or ions per liter.

The pressure of the gas will be the same as the atmospheric pressure, which will be obtainedby your instructor from the barometer located in the lab.

Submerge as much of the flak as possible in the boiling water bath, but avoid immersing the cover or allowing boiling water to splash underneath it, where it might become trapped.

Prepare an ice-water bath. A gaseous sample weighing 0. Definition - Molar concentration or molarity is most commonly in units of moles of solute per liter of solution.

What is the molar mass of the gas? When all of the liquid has evaporated and no morevapor seems to be escaping, the flask is removed form the water bath, immediately cooled, andweighed.

The volume of the gas is the same as thevolume of the flask. If the acid is diprotic,say like sulfuric acid then only half as much solution of acid would be needed to neutralize a volume of sodium hydroxide solution. The mass of the gas is the mass of the condensed liquid.

Leave the flask immersed in the boiling water until no more vapor can be seen streaming from the pinhole. Measure the temperature of the boiling water and remind your instructor to announce the atmospheric pressure to the class.

Convert the mass of water to volume using the density relationship between volume and mass and a value of 1. Bring the water to a gentle boil and maintain it throughout the experiment.

Molarity[ edit ] Here are a few sentences from Wikipedia that should be the outline around which the text is based! Add water as necessary to prevent the bath from going dry.

The number of moles of a substance is its weight in grams divided by its molecular weight. Rinse thevolumetric flask with acetone, add the washings to the waste container, and air dry the flask by suction. Obtain your unknown and immediately record the unknown number on your data sheet.

When the cooled flask warms to room temperature, dry it off, and weigh it on the same balance you used to obtain the tare mass. A few milliliters of a volatile liquid are placed in avolumetric flask which is tightly covered with aluminum foil in which a small hole is made.

The usefulness of this concept of molarity is that one liter of say one molar acid will neutralize one liter of one molar of base when the acid has one proton per molecule and the base one hydroxide per molecule. Do at least one more determination by carefully removing the foil, replenishing the liquid with another 5 - 10 mL portion of your unknown liquid, replacing the foil, and repeating the above procedure.EXPERIMENT #10Determining the Molar Mass of a Volatile LiquidOBJECTIVES: Obtain precise and accurate masses Follow directions to match experimental conditions Determine the volume of a container Carefully measure the mass of a condensed gas Apply the ideal gas equation to experimental data Determine the molar mass of an.

Chemistry for Idiots, Humans and Rebels/Mole Concept/Molarity

Calculate the molar mass of the compound. The freezing point of the solution is to make a solution that freezes at oC.

EXPERIMENT #10 Determining the Molar Mass of a Volatile Liquid

C2H6O oC and its molal freezing point constant is g of a nonelectrolyte are dissolved in Learn Determination of Molar Mass by Vapour Density with free interactive flashcards.

Choose from different sets of Determination of Molar Mass by Vapour Density flashcards on Quizlet. Log in Sign up. Experiment Molar Mass Determination by Depression of the Freezing Point Questions.

An investigation to determine the effect of an increase in molar mass on the enthalpy change of combustion of fuels. Method Variables: Independent Variable: Molar mass (type) of alcohol. the water will need to be stirred in every experiment as to prevent any anomalous results.

Experiment: Molar Mass By Freezing Point Depression Objectives • The molar mass of an unknown compound will be determined using freezing point depression. Start studying Experiment The Standardization of a Basic Solution and the Determination of the Molar Mass of a Acid.

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An experiment to demonstrate the concept of molar mass and to introduce the combination of variables
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