Gas Stoich Honors
PROCEDURE
1. Measure and cut a piece of magnesium ribbon 3.5 to 4.5 cm long. Do not exceed 4.5 cm. 2. Measure the mass of the magnesium ribbon to the nearest milligram (0.001 g) and record the mass. 3. Fold up the magnesium ribbon into a small, tight bundle. Tie it with a piece of thread (10 to 15 cm long). 4. Add about 10 mL of 3.0M HCl to a gas collection tube. 5. Hold the gas collection tube at an angle as you fill it completely with tap water, until it is nearly overflowing. Holding the tube at an angle allows the air bubbles to escape. 6. Place the magnesium in the mouth of the gas collection tube so that it is about three cm below the surface of the water. Fold the thread extension over the side of the tube. Insert a one-hole stopper into the opening so that the magnesium ribbon is held firmly in place. 7. Fill a 400-mL beaker half full with water. 8. Holding your finger over the hole in the rubber stopper, invert the tube into the 400-mL beaker of water. Clamp the gas collection tube in place on the ring stand so that the stoppered end of the tube is under the water but not touching the bottom of the beaker.
Warning: Even though the acid has been diluted by the water, be sure to wash your hands after handling the gas collection tube. 9. Observe the reaction. When no more hydrogen bubbles are visible, the reaction is complete. Tap the tube gently to release any hydrogen gas bubbles on the side of the tube. 10. Wait an additional five minutes so that the hydrogen gas reaches room temperature. 11. Cover the hole in the stopper with your finger and transfer the tube to a large cylinder filled with water. Lower or raise the tube until the liquid level on the inside of the tube is the same as the outside. Record the volume of the hydrogen gas inside the gas collection tube. (Be sure to read the liquid level at eye level.) 12. Measure and record the temperature and pressure of the lab room. 13. Obtain the
1. Measure and cut a piece of magnesium ribbon 3.5 to 4.5 cm long. Do not exceed 4.5 cm. 2. Measure the mass of the magnesium ribbon to the nearest milligram (0.001 g) and record the mass. 3. Fold up the magnesium ribbon into a small, tight bundle. Tie it with a piece of thread (10 to 15 cm long). 4. Add about 10 mL of 3.0M HCl to a gas collection tube. 5. Hold the gas collection tube at an angle as you fill it completely with tap water, until it is nearly overflowing. Holding the tube at an angle allows the air bubbles to escape. 6. Place the magnesium in the mouth of the gas collection tube so that it is about three cm below the surface of the water. Fold the thread extension over the side of the tube. Insert a one-hole stopper into the opening so that the magnesium ribbon is held firmly in place. 7. Fill a 400-mL beaker half full with water. 8. Holding your finger over the hole in the rubber stopper, invert the tube into the 400-mL beaker of water. Clamp the gas collection tube in place on the ring stand so that the stoppered end of the tube is under the water but not touching the bottom of the beaker.
Warning: Even though the acid has been diluted by the water, be sure to wash your hands after handling the gas collection tube. 9. Observe the reaction. When no more hydrogen bubbles are visible, the reaction is complete. Tap the tube gently to release any hydrogen gas bubbles on the side of the tube. 10. Wait an additional five minutes so that the hydrogen gas reaches room temperature. 11. Cover the hole in the stopper with your finger and transfer the tube to a large cylinder filled with water. Lower or raise the tube until the liquid level on the inside of the tube is the same as the outside. Record the volume of the hydrogen gas inside the gas collection tube. (Be sure to read the liquid level at eye level.) 12. Measure and record the temperature and pressure of the lab room. 13. Obtain the