QR Challenge: Gasses

Created using the ClassTools QR Treasure Hunt Generator

Teacher Notes

A. Prior to the lesson:

1. Arrange students into groups. Each group needs at least ONE person who has a mobile device.

2. If their phone camera doesn't automatically detect and decode QR codes, ask students to

• Download a QR reader (e.g. I-Nigma | NeoReader | Kaywa) onto their mobile devices
• Bring these devices into the lesson.

3. Print out the QR codes.

4. Cut them out and place them around your class / school.

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B. The lesson:

1. Give each group a clipboard and a piece of paper so they can write down the decoded questions and their answers to them.

2. Explain to the students that the codes are hidden around the school. Each team will get ONE point for each question they correctly decode and copy down onto their sheet, and a further TWO points if they can then provide the correct answer and write this down underneath the question.

3. Away they go! The winner is the first team to return with the most correct answers in the time available. This could be within a lesson, or during a lunchbreak, or even over several days!

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C. TIPS / OTHER IDEAS

4. A detailed case study in how to set up a successful QR Scavenger Hunt using this tool can be found here.

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Questions / Answers (teacher reference)

Question	Answer
1. 1. Give the Boyle’s Law equation.	P1V1 = P2V2
2. 2. A metal cylinder contains 1 mol of nitrogen gas at STP. What will happen to the pressure if another mole of gas is added to the cylinder but the temperature does not change?	The pressure of the gas will increase.
3. 3. A gas with a volume of 4L at a pressure of 90 kPa is allowed to expand until the pressure drops to 20 kPa. What is the new volume?	V2 = 18L
4. 4. The volume of a gas is 204 cm3 when the pressure is 925 kPa. At constant temp, a change in pressure causes the volume of the sample to change. If the new volume is 306 cm3, what must the pressure have been changed to?	P2 = 616.67kPa
5. 5. Five liters of air at -36 degrees C is warmed to 89 degrees C. What is the new volume if the pressure remains constant?	V2 = 7.64L
6. 6. A gas with a volume of 300 mL at 150 C is heated until its volume is 600 mL. What is the new temperature of the gas if the pressure is unaltered?	T2 = 846 K
7. 7. If a sample of a gas is heated, what will happen to its volume?	The volume will increase.
8. 8. You blow up a balloon and tie it off. You then place this balloon in a freezer. What will happen to this balloon after it has remained in the freezer for some period of time? Why?	The balloon will shrink. As the gas inside the balloon cools, the volume of the gas will decrease.
9. 9. Why would it be dangerous to heat a tightly stoppered flask?	As the temperature increases inside the tightly stoppered flask, the pressure of the gas will continue to increase until the stopper is blown from the flask.
10. 10. A gas cylinder contains nitrogen gas at 1000 kPa pressure and a temperature of 20 degrees C. The cylinder is left in the sun, and the temperature of the gas increases to 50 degrees C. What is the pressure in the cylinder?	P2 = 1102.39 kPa
11. 11. What is STP?	STP Stands for Standard Temperature, 273K, and Pressure, 101.3 kPa, 1 atm, or 760 mmHg.
12. 12. At constant temperature, what will happen to the pressure of a gas if the volume of the gas is increased?	The pressure will decrease.
13. 13. State Boyle’s Law.	The volume of a sample of gas is inversely proportional to its pressure, if the temperature remains constant.
14. 14. State Charles’s Law.	Charles’s Law states that the volume of a fixed mass of gas is directly proportional to its Kelvin temperature, if the pressure remains constant.
15. 15. When is the combined gas law used?	The combined gas law is used when one needs to know the volume of a gas when both the temperature and the pressure are changed.

 

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