The crux of the problem asks you to compute the elastic modulus of a pancake--for this we give you numbers that we got from our own measurements of the pancakes. The last question asks you to hypothesize about which ingredients are playing the role of flour in the gluten free recipes. If you find this topic interesting, you may want to consider exploring something like this for your final project, and design an experiment to understand the difference between the normal and gluten free recipe and try to manipulate the gluten free recipe to better resemble the normal pancakes. If you choose to make the two recipes and compare them in your own kitchen, make sure you use exactly the same protocol for each recipe: In our trials, we made the batter, and then cooked on a skillet, using 1/4 cup of batter per pancake, and flipped when the edges were firm and golden, about 4-5 minutes on each side. Consider a stack of six pancakes. Each pancake is made of 1/4 cup (approximately 60 mL) of batter, and the density of batter is 1 g/cm3. Consider the pancake at the bottom of the stack. What is the total weight of pancakes sitting on top of it? Express your answer in kilograms, but without entering the unit. This is not a lot of weight. Assuming that pancakes have an elastic modulus of 20 kPa, that the area of each pancake is identical (approximately 80 ), and that the stack of pancakes has a height of 55mm, compute how much the single pancake at the bottom of the stack is compressed by the weight of the pancakes on top of it. This is a very small compression, so instead you place a 4 kg weight on the pancakes. Now you see that the stack noticeably compresses. Consider the stack of pancakes as one aggregate unit with a surface area of approximately 80 cm2. What is the stress on the pancakes? Express your answer in Pascals, but without including the unit. Your observation of the normal pancakes shows that when the 4kg weight is placed on the pancakes, the height of the pancake stack decreases from its initial value of 55mm to a final value of 40mm. Use these measurements to calculate the elastic modulus of the pancakes. Express your answer in Pascals but without giving the units as part of your answer.

The crux of the problem asks you to compute the elastic modulus of a pancake--for this we give you numbers that we got from our own measurements of the pancakes. The last question asks you to hypothesize about which ingredients are playing the role of flour in the gluten free recipes. If you find this topic interesting, you may want to consider exploring something like this for your final project, and design an experiment to understand the difference between the normal and gluten free recipe and try to manipulate the gluten free recipe to better resemble the normal pancakes.
If you choose to make the two recipes and compare them in your own kitchen, make sure you use exactly the same protocol for each recipe: In our trials, we made the batter, and then cooked on a skillet, using 1/4 cup of batter per pancake, and flipped when the edges were firm and golden, about 4-5 minutes on each side.
Consider a stack of six pancakes. Each pancake is made of 1/4 cup (approximately 60 mL) of batter, and the density of batter is 1 g/cm3. Consider the pancake at the bottom of the stack. What is the total weight of pancakes sitting on top of it? Express your answer in kilograms, but without entering the unit.
This is not a lot of weight. Assuming that pancakes have an elastic modulus of 20 kPa, that the area of each pancake is identical (approximately 80 ), and that the stack of pancakes has a height of 55mm, compute how much the single pancake at the bottom of the stack is compressed by the weight of the pancakes on top of it.
This is a very small compression, so instead you place a 4 kg weight on the pancakes. Now you see that the stack noticeably compresses. Consider the stack of pancakes as one aggregate unit with a surface area of approximately 80 cm2. What is the stress on the pancakes? Express your answer in Pascals, but without including the unit.
Your observation of the normal pancakes shows that when the 4kg weight is placed on the pancakes, the height of the pancake stack decreases from its initial value of 55mm to a final value of 40mm. Use these measurements to calculate the elastic modulus of the pancakes. Express your answer in Pascals but without giving the units as part of your answer.
Given your measurement of the elastic modulus, what is the distance between the bonds in the normal pancakes? Assume that the interaction energy between the glutenin molecules is 
 
Larger than 1 micron
 
between 100 nm and 1 micron
 
Between 10 nm and 100 nm
 
Between 1 nm and 10 nm
 
Smaller than 1 nm

Your observation of the gluten-free pancakes shows that they are much softer. For that reason you only use a 0.7 kg weight. Now the height of the pancake stack decreases from its initial value of 55 mm to a final value of 46 mm. Use these measurements to calculate the elastic modulus of the pancakes. Express your answer in Pascals but without including the unit.
Given your measurement of the elastic modulus, what is the distance between the bonds in the gluten-free pancakes? Assume that the interaction energy between the molecules in the gluten free pancake recipe is 
The cross link distance is
 
Larger than 1 micron
 
between 100 nm and 1 micron
 
Between 10 nm and 100 nm
 
Between 1 nm and 10 nm
 
Smaller than 1 nm

PANCAKES
This assignment has several steps. In the first step, you'll provide a response to the prompt. The other steps appear below the Your Response field.

This is a self-assessment question and you will be graded on a rubric of 0-6 points. Please submit your answer and assign yourself points based on the rubric.

Review a "standard" pancake recipe as well as one for gluten-free pancakes (such as those linked above). Which ingredient(s) in the gluten-free recipe do you think are fulfilling the role of the missing gluten? Briefly explain how this ingredient (or these ingredients) compensate for the absence of gluten.
How would you carry out an experiment to test your hypothesis that this ingredient (or these ingredients) are used to compensate for the absence of gluten? What result would tell you that your hypothesis is correct?