Q. 3.33 - An Introduction to General, Organic, and Biological Chemistry

Question

For dinner, Charles had one cup of clam chowder, which contains$16 g$ of carbohydrate, $12 g$ of fat, and $9 g$ of protein. How much energy, in kilocalories and kilojoules, is in the clam chowder? (Round off the answer for each food type to the tens place.)

Step-by-Step Solution

Answer

The amount of energy in cup of clam chowder is $880 kJ.$

Step: 1 Given information:

Given are: $16g$of carbohydrate, $12g$ of fat, and $9g$ of protein of one cup of clam chowder .

To find the energy in kilocalories and kilojoules in the clam chowder.

Step: 2 Converting:

The total energy in a bowl of clam chowder is the sum of the energy associated with each gramme of individual component. To get the overall energy, add the energy associated with each individual clam chowder ingredient.

Where energy in per gram is

Carbohydrates $=4\mathrm{kcal}/\mathrm{g}$

Fats $=9kcal/g$

Protein $=4\mathrm{kcal}/\mathrm{g}$

Step: 2 Equating:

Calculating energy in cup of clam chowder

Carbohydrates energy   $=(4\mathrm{kcal}/\mathrm{g})\times \left(16\mathrm{g}\right)$ $=64 kcal$

Fat energy  $=(9\mathrm{kcal}/\mathrm{g})\times \left(12\mathrm{g}\right)$ $=108 kcal$

Protein energy  $=(4\mathrm{kcal}/\mathrm{g})\times \left(9\mathrm{g}\right)$ $=36 kcal$

Amount of energy in per cup is 

$=(64+108+36)\mathrm{kcal}$

$=208 kcal$

Rounding off values$=210kcal.$

Step: 4 Clam chowder energy:

The factor conversion is

$1 kcal =4.184 kJ$

$210\mathrm{kcal}=\left(\frac{210\mathrm{kcal}}{1\mathrm{kcal}}\right)\times 4.184\mathrm{kJ}$

$210 kcal=878.64 kJ$

Rounding off the value is $880 kJ.$