Warming up with energy

1. Warming up with energy Lesson objectives * know the difference between temperature and heat * Find out through experiment; the power of a bunsen burner

2. Warming up with energy

5. Experiment to compare boiling times for different amounts of water For 50 cm3 water Time / min Temp / C 0.0 18 1.0 50 2.0 80 3.0 92 4.0 100 Prediction: ……………………………………………………….. thermometer 50cm3 water HEAT ……………………………………………………….. Conclusion:

6. Temp / C 100 80 60 40 20 TIME / mins 0 8 4 2 6

7. For 50 cm3 water Time / min Temp / C 0.0 18 1.0 50 2.0 80 3.0 92 4.0 100 Temp / C 100 80 60 40 20 TIME / mins 0 8 4 2 6

8. Temp / C 100 80 For 50 cm3 water 60 Time / min Temp / C 0.0 18 40 1.0 50 2.0 80 3.0 92 20 4.0 100 TIME / mins 0 8 4 2 6

9. Temp / C 100 80 Gradient = Δ temp Δ time 60 40 20 TIME / mins 0 8 4 2 6

10. Temp / C 100 80 Gradient = Δ temp = Δ T Δ time Δ t 60 40 20 TIME / mins 0 8 4 2 6

11. Temp / C 100 80 Gradient = Δ temp = Δ T Δ time Δ t = (68 -33) C 60 sec = 60 40 20 TIME / mins 0 8 4 2 6

12. Temp / C 100 80 Gradient = Δ temp = Δ T Δ time Δ t = (68 -33) C 60 sec = 0.58 C / sec 60 40 20 TIME / mins 0 8 4 2 6

13. Temp / C 100 Bunsen power: (assuming no energy loss) Δ U = m c Δ T Δ t Δ t = 80 Gradient = Δ temp = Δ T Δ time Δ t = (68 -33) C 60 sec = 0.58 C / sec 60 40 20 TIME / mins 0 8 4 2 6

14. Temp / C 100 Bunsen power: (assuming no energy loss) Δ U = m c Δ T Δ t Δ t = 0.05 x 4200 x 0.58 = 80 Gradient = Δ temp = Δ T Δ time Δ t = (68 -33) C 60 sec = 0.58 C / sec 60 40 20 TIME / mins 0 8 4 2 6

15. Temp / C 100 Bunsen power: (assuming no energy loss) Δ U = m c Δ T Δ t Δ t = 0.05 x 4200 x 0.58 = 121 W 80 Gradient = Δ temp = Δ T Δ time Δ t = (68 -33) C 60 sec = 0.58 C / sec 60 40 20 TIME / mins 0 8 4 2 6