The following questions concern the iconic Nestle Toll House Chocolate Chip Cookie recipe, shown below:
2 1/4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon salt
1 cup butter or margarine, softened
3/4 cup granulated sugar
3/4 cup packed brown sugar
1 teaspoon vanilla extract
2 large egg
1 (12 ounce) package NESTLE® TOLL HOUSE® Semi-Sweet Chocolate Morsels
1 cup chopped nuts
1)Baking soda consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.
2)Granulated sugar consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.
3)Table salt consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.
4)Glutenin (molecular weight: 75,000amu) makes up ~60% of the protein in all-purpose flour. About how many molcules of glutenin are in this recipe?
5 answers
2. sucrose. You can look up the other items.
3. NaCl. You can look up the other items.
4. 75,000 grams will contain 6.02E23 molecules.
We know the density of flour is ρflour = 100 g/ 170 mL = .59 g/mL. To find the mass of flour, mflour we can multiply ρflour by the total volume of flour, Vflour:
Vflour=2.25 cups⋅237 ml/cup=533 mL
mflour=ρflour⋅Vflour=59 g/mL⋅533 mL=314 g
Now that we have the mflour, we can find the mass of the glutenin, mglutenin, since we know that flour is 60% glutenin by mass:
mglutenin=mflour⋅10 g protein100 g flour⋅60 g glutenin100 g protein=18.84 g glutenin
We can divide mglutenin by its molecular weight, mwglutenin = 75,000 g/mol to find the moles. To find the number of molecules we can multiply the moles by Avogadro's number, NA = 6.022 ⋅ 1023 molecules/mole.
Molecules of glutenin: =mglutenin75,000 g/mol⋅6.022⋅1023 molecules/mol=1.5⋅1020 molecules
2 1/4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon salt
1 cup butter or margarine, softened
3/4 cup granulated sugar
3/4 cup packed brown sugar
1 teaspoon vanilla extract
2 large egg
1 (12 ounce) package NESTLE® TOLL HOUSE® Semi-Sweet Chocolate Morsels
1 cup chopped nuts
1)Baking soda consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.
2)Granulated sugar consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.
3)Table salt consists mostly of a single chemical. Look up what it is, its molecular weight and density, and determine the number of moles used in this recipe.