Skip to main content
Ch.5 - Thermochemistry
Chapter 5, Problem 91a

(a) A serving of a particular ready-to-serve brown & wild rice meal contains 4.5 g fat, 42 g carbohydrate, and 4.0 g protein. Estimate the number of calories in a serving.

Verified Solution

Video duration:
7m
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Caloric Content of Macronutrients

Each macronutrient provides a specific number of calories per gram: fats provide 9 calories per gram, carbohydrates provide 4 calories per gram, and proteins also provide 4 calories per gram. Understanding these values is essential for calculating the total caloric content of a food item based on its macronutrient composition.
Recommended video:
Guided course
06:35
Effective Nuclear Charge Calculation with Slater's Rules

Caloric Calculation

To estimate the total calories in a food serving, multiply the grams of each macronutrient by its respective caloric value and then sum the results. This calculation allows for a straightforward determination of the energy content of the meal based on its nutritional breakdown.
Recommended video:
Guided course
02:28
Stoichiometric Rate Calculations

Nutritional Labeling

Nutritional labeling provides essential information about the macronutrient composition of food products. Understanding how to read and interpret these labels is crucial for making informed dietary choices and for performing calculations related to caloric intake.
Recommended video:
Guided course
01:14
Nature of Energy
Related Practice
Textbook Question

(a) The nitrogen atoms in an N2 molecule are held together by a triple bond; use enthalpies of formation in Appendix C to estimate the enthalpy of this bond, D(N‚N). (b) Consider the reaction between hydrazine and hydrogen to produce ammonia, N2H41g2 + H21g2¡2 NH31g2. Use enthalpies of formation and bond enthalpies to estimate the enthalpy of the nitrogen– nitrogen bond in N2H4. (c) Based on your answers to parts (a) and (b), would you predict that the nitrogen–nitrogen bond in hydrazine is weaker than, similar to, or stronger than the bond in N2 ?

1628
views
Textbook Question

Consider the reaction 2 H2(g) + O2(g) → 2 H2O(l). (a) Use the bond enthalpies in Table 5.4 to estimate H for this reaction, ignoring the fact that water is in the liquid state.

499
views
Textbook Question

(b) A particular chip snack food is composed of 12% protein, 14% fat, and the rest carbohydrate. What percentage of the calorie content of this food is fat?

1241
views
Textbook Question

The heat of combustion of fructose, C6H12O6, is -2812 kJ/mol. If a fresh golden delicious apple weighing 120 g contains 16.0 g of fructose, what caloric content does the fructose contribute to the apple?

1493
views
Textbook Question

The heat of combustion of ethanol, C2H5OH(l), is -1367 kJ/mol. A bottle of stout (dark beer) contains up to 6.0% ethanol by mass. Assuming the density of the beer to be 1.0 g/mL, what is the caloric content due to the alcohol (ethanol) in a bottle of beer (500 mL)?

4703
views
Textbook Question

The standard enthalpies of formation of gaseous propyne (C3H4), propylene (C3H6), and propane (C3H8) are +185.4, +20.4, and -103.8 kJ/mol, respectively. (b) Calculate the heat evolved on combustion of 1 kg of each substance.

597
views