This experience is designed to teach methods for measuring the volume of different material states: liquid, solid, and gas, using specific techniques and equipment for each case. It makes it possible to understand the principles of measurement and the physical properties of matter through practical methods.
Part 1: Measure the volume of a liquid. This part demonstrates how to precisely measure the volume of a liquid using a graduated cylinder. The meniscus technique is essential to obtain precise reading because it considers the curvature that the liquid forms on the surface due to the surface tension forms.
Part 2: Measure the volume of a solid by movement of water. This method uses the principle of Archimedes, which stipulates that the volume of fluid moved is equal to the volume of the submerged object. By measuring overflowed water when a solid is immersed in a too full vase, you can determine the volume of the solid. It is a particularly useful technique for irregular solids that cannot be measured directly by a rule or a caliber.
Part 3: Measure the volume of gas. Measuring the volume of a gas uses a gas buret submerged in water, allowing gas to replace water in the buret. This method illustrates how gases can be contained, and their volume measured by moving another fluid. It depends on the atmospheric pressure and the capacity of the gas to occupy all the available space, in accordance with the laws of gas.
Educational Goals
Practice specific measurement methods: students learn to use different measuring instruments and correctly interpret the readings to obtain specific results.
Understanding the properties of matter: experience illustrates the fundamental physical properties of the different states of matter, such as the capacity of liquids to form a meniscus, the solidity of the solids which allows them to move water, and the expansibility of gas.
Apply physical principles: steps involve the application of physical principles, such as the principle of Archimedes for solids and gas laws to measure the volume of gases.
By combining theory and practice, this experience educates on basic measurement techniques in physics and chemistry, while strengthening understanding of the properties of matter in its different states.
Protocol
Part 1: Measuring the volume of a liquid
1. Using the sink, measure 70 mL of liquid in the appropriate graduated cylinder.
2. Check the base of the meniscus in the graduated cylinder to confirm the volume.
Part 2: Measuring the volume of a solid using an overflow vessel
To measure the volume of a solid, we can use water displacement.
3. Fill an overflow vessel to its full capacity before overflowing (500 mL).
4. Place a 25 mL graduated cylinder under the overflow spout of the vessel.
5. Drop 5 pieces of iron (III) nitrate into the overflow vessel using tongs.
6. Using the overflow from the vessel and the meniscus in the graduated cylinder, determine the volume of the solid.
Part 3: Measuring the volume of a gas
To measure the volume of gas, we can use a gas buret.
7. Fill a 1 L beaker with 700 mL of tap water.
8. Position this beaker next to the stand.
9. Install a universal clamp above the center of the beaker to support the gas buret.
10. Fill the gas buret with water.
11. Holding the buret upside down, block its opening with your thumb.
12. Place the inverted gas buret in the clamp, ensuring its opening is near the bottom of the beaker.
13. Gently release your thumb to allow the buret to be submerged without losing water.
14. Adjust the setup if necessary to prevent water loss from the buret.
15. Attach a “J” shaped plastic connector under the opening of the gas buret.
16. Connect the blue hose from the gas cylinder to the connector and start the timer.
17. Open the valve of the gas cylinder.
18. Allow the gas buret to fill halfway with gas. This should take about a minute.
19. Close the gas valve and read the volume on the gas buret.
Anticipated Outcomes
This is a practical session to familiarize yourself with the use of the graduated cylinder, the overflow vessel, and the gas buret.
5 pieces of Fe(NO3)3 (s) will occupy a volume of: 5 x 1.78g x 1.68g/mL = 14.95mL
Summary of Assignment by Grade Range
Grades 3-5 (Ages 8-10)
- Focus: Basic introduction to measurement techniques and understanding matter properties.
- Activities: Using graduated cylinders for liquids, simple water displacement for solids.
Grades 6-8 (Ages 11-13)
- Focus: Developing measurement skills and applying basic physical principles.
- Activities: Precision in using graduated cylinders, applying Archimedes’ principle, introduction to gas volume measurement.
Grades 9-12 (Ages 14-18)
- Focus: Mastering measurement techniques and understanding advanced physical principles.
- Activities: Advanced use of graduated cylinders, detailed application of Archimedes’ principle, precise gas volume measurement.
Laboratory essentials
Instruments
Beaker (1000 ml)
Gaz buret
Gaz connector
Gaz tank
Graduated cylinders (10 ml, 25 ml, 70 ml, 250 ml)
Lab Stand & Clamps
Overflow Vessel
Spatula
Tweezers
Timer
Products
Iron (III) nitrate (pieces). (pieces)