Show All Work for the Calculations in This Lab

Lab: Determine Pressure in Popcorn Kernels

Data Table

Water Volume 5.00 mL Total volume of water and popcorn 10.00 mL Volume of kernels 5.00 mL = 0.005L Mass of beaker, oil and kernels before popping 97.00 g Mass of beaker, oil and kernels after popping 96.50 g Mass of Water lost 0.50 g Number of moles water lost 0.0277 mol

Calculations (QUESTIONS 1-4 under Analyze and Conclude. You do not need to write the questions )

SHOW ALL WORK FOR THE CALCULATIONS IN THIS LAB

Be sure to use the room pressure listed for your class!

1. Mole of water lost = 0.50g/18g/mol = 0.0277 mol

2. Room Pressure: (743 torr = 0.977 atm)

Conversion factor: 1 atm = 760 torr or 1 atm = 760 mmHg

R = 0.0821l.atm/mol.K

Temperature of oil = 225oC = 498 K

PV = nRT

P = nRT/V = (0.0277 mol x 0.0821 L.atm/mol.K x 498 K) ______= 227 atm 0.005L

Popping Pressure to Atmospheric Pressure Ratio = 227atm/ 0.977 atm =

Analysis (Write and answer the questions below )

1) Compare and contrast atmospheric pressure to the pressure of the water in the kernel. (Explain what the pressure ratio means)

2) Infer why all the popcorn kernels did not pop.

3) Explain why the farmer is able to store kernels for months or years without popping.

4) Error Analysis. Identify a potential source of error for this lab, and suggest a method to correct it. Conclusion

In this section, you should summarize your findings. Include the results and data supporting your hypothesis. Write clearly and concisely using complete sentences. Be specific. Avoid using vague pronouns that force the reader to guess what you’re describing. Always use third person (NO personal pronouns --- me, I, you, we, etc.) when writing all parts of a lab. (USE HE, SHE, THEY, THEIR, THEM, ETC.) Hypothesis is rejected or accepted based on the data. Discuss potential sources of error for this lab, and suggest methods to correct it. This is the most important part of the report. It’s where you tie everything together and show me what you know.