Concentrated Hcl and Magnesium React in a Eudiometer Tube

Concentrated HCl and Magnesium React In A Eudiometer Tube

Spencer Barber

Chemistry Honors, Period 2

Lab Partner: Megna Ray

May 11, 2014

Mr. Isaac

1.    Introduction:

        A gas is defined as a state of matter having neither a fixed shape nor volume. Gases take the shape of their container and are easily compressible but when compressed, exert high amounts of pressure. Gases in an open room exert little pressure and are spaced from each other but when gases are compressed, they exert high amounts of pressure because there are many molecules in a small container. Liquids are another state of matter and they fix to the shape of their container and cannot be compressed. This means that during an aqueous reaction in which a gas is produced, the appearance of bubbles can be seen. In the case of concentrated hydrochloric acid reacting with magnesium, hydrogen gas is produced. The reaction is a single replacement reaction in which the HCl reacts with magnesium to form magnesium chloride and hydrogen gas. The balanced chemical equation is as follows: Mg (s) +2HCl (aq) yields MgCl2 (aq) +  H2 (g). To test if the gas is really hydrogen, a simple test can be done to prove it is hydrogen. Capture the gas in a test tube and light a match and if there is a distinct barking sound, then there is hydrogen in the container. The formula PV=nRT is called the ideal gas law and it is used to find the moles of a substance. It is a combination of Boyle’s, Charles’s and Gay Lussac’s Law altogether. Using the ideal gas law, the objective of the experiment is to determine the ideal gas law constant.

2.    Materials/Chemicals

• Digital Balance
• Magnesium Ribbon
• Eudiometer Tube
• Copper Wire
• Concentrated hydrochloric acid
• Battery Jar
• Distilled Water
• Tap Water
• Utility Clamp
• Thermometer
• Meter Stick

3.    Procedure

1. Obtain roughly .8 grams of a magnesium ribbon
2. Wrap the copper wire around the top of the eudiometer tube and securely wrap the other end of the copper wire to the magnesium so that the magnesium is inside the eudiometer tube
3.  Your teacher should have already placed the HCl in the eudiometer tube so fill the tube with distilled water until the tube is almost overflowing.
4. Fill a battery jar full of tap water.
5. Carefully place your thumb over the top of the eudiometer tube and in a fluid motion, place the open end of the tube into the batter jar full of water
6. Use the utility clamp to hold the eudiometer tube in place while it is in the water (make sure that the tube is parallel with the bottom of the battery jar or else hydrogen gas will escape and skew your results)
7. Allow the reaction to take place until the magnesium is fully reacted (the HCl will diffuse down the tube and react with the magnesium)
8. Once the reaction is complete, use a meter stick and measure how much gas is in the container.
9. Record the temperature of the water every minute three times
10. Record the atmospheric pressure using either a barometer or the national weather service website

4.    Safety

• Be careful with glassware
• Concentrated HCl is very corrosive, tell your teacher immediately if you were to come in contact with it
• Always wear safety goggles

5.    Observations and Data Tables

Table 1: Substances and amounts        

6.    Calculations

7.    Conclusion