Do you want to do more labs and activities but have little time and resources? Are you frustrated with traditional labs that are difficult for the average student to understand, time consuming to grade and stressful to complete in fifty minutes or less?
Teacher friendly labs and activities meet the following criteria:
- Quick set up with flexibility of materials and equipment
- Minutes in chemical preparation time
- Cheap materials that are readily available
- Directions written with flexibility of materials
- Minimal safety concerns
- Can be easily and safely stored as a kit
- Quick and easy to photocopy
- Specific learning objectives
- During the lab students are self reliant
Introduction to Gas Laws Lab NAME:______________________________DATE:_____________PERIOD:__ _____
Background:
In a gas, particles are spread far apart; therefore a gas takes up more volume than a solid or a liquid. For example, water in the form of steam takes up about 2000 times the volume that the same amount of water does in liquid form.
There are many formulas to describe the behavior of a gas under certain conditions. Boyle's Law, PV=k, states that the pressure is inversely proportional to the volume. Charles's Law, V/T =k, states that volume is directly proportional to the temperature. Gay-Lussac's Law, P/T =k, states that pressure is directly proportional to the temperature. Relationships that are directly proportional produce a straight line graph, while inversely proportional relationships produce a curve. Applying these laws to compare gases under two different sets of conditions gives the formulas: P
1V
1=P
2V
2 V
1/T
1=V
2/T
2 P
1/T
1 =P
2/T
2 These three laws together give the Combined Gas Law: P
1V
1/T
1 = P
2V
2/T
2.
Procedure & Observations:
Part 1 1) Obtain a large beaker (600-1000 mL) and fill 3/4 full of tap water.
2) Obtain an aluminum can and add 7-10 milliliters of water.
3) Place the can on a heating set up (hotplate or wire gauze/ring stand) and heat until a steady stream of steam flows out of the can.
4) Using beaker tongs, grab the aluminum can near the bottom of the can and quickly turn it upside down into the beaker of water.
Observation:
When the can was heated, the water turned to ___________, which takes up ________ (more/less) volume than liquid water. When the can was inverted into the water this created a closed system. The temperature inside the can ___________ (increased/decreased), causing the steam to change from gas state to ______________state. A partial vacuum was created causing the pressure inside the can to be ______________ (greater/less) than the pressure outside the can.