Q.3.58 - An Introduction to General, Organic, and Biological Chemistry

Question

a. During one week, Charles swam for a total of 2.5h and walked for a total of 8h. If Charles expends 340kcal/h swimming and 160kcal/h walking, how many total kilocalories did he expend for one week?

b. For the amount of exercise that Charles did for one week in part a, if expending 3500 kcal is equal to a loss of 1.0 lb, how many pounds did he lose?

c. How many hours would Charles have to walk to lose 1.0 lb?

d. How many hours would Charles have to swim to lose 1.0 lb?

Step-by-Step Solution

Answer

a. $2130kcal$

b. he lost $0.608lb$

c. Charles has to walk $22hrs$

d. Charles has to swim $10.3hrs$

Step 1: introduction

A calorie is a unit of energy. In sustenance, calories allude to the energy individuals get from the food and drink they polish off, and the energy they use in active work. Calories are recorded in the nourishing data on all food bundling. Many health improvement plans are based on lessening the admission of calories.

Step 2: explanation part (a)

Given,

time for swimming is $2.5hr$ and time for walking is $8hr$

calories burned while swimming = $340kcal$

calories burned while walking = $160kcal$

$\text{ Total}\text{ kcal expended}=\text{ Energy spent due to swimming }+\text{ Energy spent due to walking }$

$=2.5\mathrm{h}\times 340+8.0\mathrm{h}\times 160=2130kcal$

Step 3: explanation part (b)

Loss of $1lb$took $3500kcal$

total energy is $2130kcal$

total weight lost,

$\frac{2130}{3500}=0.608lb$

Step 4: explanation part (c)

$160kcal$ burned while walking for $1hr$

Total calories to be burned = $3500kcal$

The time taken to burn them,

$\frac{3500}{160}=22h$

Step 4: explanation part (d)

Given,

calories required to burn$1lb=3500kcal$

calories burned per hour while swimming = $340kcal$

Time taken for Charles to lose $1lb$ while swimming =

$\frac{3500}{340}=10.3\mathrm{hr}$