J 5A Molar Volume Lab Molar volume is the volume occupied by one mole of gas collected at standard temperature and pressure or STP.

Materials Needed Eudiometer 400 ml beaker Ring stand Buret clamp Two hole rubber stopper Copper wire

Chemicals Needed Magnesium ribbon, 3.5 – 4.0 cm length 6 M Hydrochloric Acid

Read the procedure. Assemble all equipment. Magnesium ribbon Copper Wire

Measure the magnesium ribbon.

Use an analytical balance to get the mass of the magnesium ribbon.

Pour 10 ml of 6M HCl directly into the eudiometer Pour 10 ml of 6M HCl directly into the eudiometer. Use the graduations on eudiometer to measure.

Fill the eudiometer all the way to the brim with distilled water.

Curl the magnesium ribbon and secure to the copper wire.

The magnesium is attached to the copper on the rubber stopper.

The rubber stopper is placed in the end of the eudiometer. Magnesium ribbon

The eudiometer is inverted in a beaker of water.

Allow the magnesium ribbon and the HCl to react in the eudiometer until the reaction is complete.

Bubbles begin to form at the magnesium ribbon.

As the reaction advances the bubbles become more intense. Increased Bubbles

As gas forms, the water is pushed out of the eudiometer through the holes in the rubber stopper. Pocket of Gas

This is the amount of gas that has been collected in the eudiometer. Read the ml

Place the eudiometer in a large graduated cylinder filled with water.

Keep one finger over the holes in the rubber stopper when placing the eudiometer in the graduated cylinder.

Make the water level inside tube be on the same level as the water level in the graduated cylinder. Level inside cylinder

The two levels are the same for the final reading.

Final reading for the volume of the gas in the eudiometer.

Read the barometric pressure Mercury level

800 mmHg Level of mercury 700 mmHg

54 mmHg 700 mmHg

Take the reading on the thermometer.

Final Calculations Read the volume of the gas collected in the eudiometer and record in the data table. Record the barometric pressure. Record the room temperature. Determine the water vapor pressure using a water vapor pressure table.