- 1). Place a funnel in the graduated cylinder with the pointed end of the funnel in the cylinder. Pour the liquid you want to analyze from its original container into a 50-ml graduated cylinder. For example, you pour methyl alcohol (methanol, or wood alcohol) into a 50-ml graduated cylinder. See Resources for an online wood methanol source. Methanol is useful because it undergoes a relatively large expansion when heated.
- 2). Note the mark along the side of the graduated cylinder that is level with the bottom curve (meniscus) of the liquid level. The fluid level in a cylinder will often be curved downward at the top. This curve is called the "meniscus." Write down the number of the mark. For example, the bottom curve of the methanol surface is level with the "40" mark along the side of the cylinder. You write, "Initial volume = 40 mL."
- 3). Measure the temperature of your surroundings using a digital thermometer that measures in Fahrenheit and Celsius. Write the temperature in Celsius. For example, the temperature in your kitchen is 62.6 degrees Fahrenheit, which is the same as 17 degrees Celsius. You write, "Initial temperature = 17 C."
- 4). Take the graduated cylinder outside on a hot afternoon or place it in another warm environment such as an attic or on top of a refrigerator. Do not use an oven. This might be dangerous. Allow the liquid in the cylinder to warm for one hour.
- 5). Measure the temperature of this warmer environment and write the temperature you measure in Celsius. For example, it is 98.6 F outside your house, which is the same as 37 C. Your write, "Final temperature = 37 C."
- 6). Consult a table of coefficients of cubical expansion in a textbook or online (see Resources) and find the coefficient for the liquid you are analyzing. The coefficient will be opposite the name of the liquid you are analyzing under a column headed "Volumetric Coefficient of Expansion" with the subheading "(1/K, 1degree C)." This coefficient is a dimensionless unit that identifies how much a liquid's volume changes for each degree change in temperature in Kelvin (K) or Celsius (C). For example, you find the coefficient of cubical expansion for methanol is 0.00118.
- 7). Multiply the coefficient of cubical expansion by the initial volume of your liquid using a calculator. You must do this to find the volume change in your liquid for each one-degree change in temperature in Celsius. For example, 0.00118 x 40 = 0.0472.
- 8). Multiply your answer by the difference of the initial temperature of the liquid and the final temperature of the liquid. You must do this to find the volume change in your liquid for the total change in temperature in Celsius. For example, 0.0472 x (37 - 17) = 0.944. The expansion in the volume of the methyl alcohol was 0.944 milliliters.
- 9). Add your answer to the initial volume of the liquid. Your first number will be the amount your volume expanded. You must add this number to the original volume to discover the final volume of the liquid. This is also necessary because liquids typically do not expand much when heated, and the amount of expansion, in this case 0.944 mL, will be too small to be accurately determined using visual measurement. For example, 0.944 + 40 = 40.944. After thermal expansion, the volume of the methyl alcohol was 40.944 milliliters.
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