Question

exercise 04: thermochemistry
directions: download and print this document. answers for this assignment should be handwritten in space available in the document. you may use extra papers. limit your answers to 3 - 5 sentences and a maximum of 300 word.

1. convert the following energy units

a. 567 cal to j
b. 2.85x10³ kj to cal
c. 231 cal to kj
d. 132x10⁴ kj to kcal

Explanation:

Step1: Recall conversion factors

1 Cal = 4.184 kJ, 1 kJ = 1000 J, 1 cal = 4.184 J, 1 kcal = 1000 cal

Step2: Convert 567 Cal to J

$567\ Cal\times4.184\ kJ/Cal\times1000\ J/kJ = 567\times4.184\times1000\ J= 2.372228\times10^{6}\ J$

Step3: Convert $2.85\times10^{3}$ kJ to Cal

$(2.85\times10^{3}\ kJ)\times(1\ Cal/4.184\ kJ)\approx681\ Cal$

Step4: Convert 231 cal to kJ

$231\ cal\times(4.184\ J/cal)\times(1\ kJ/1000\ J)=231\times4.184\times\frac{1}{1000}\ kJ = 0.968504\ kJ$

Step5: Convert $1.32\times10^{4}$ kJ to kcal

$(1.32\times10^{4}\ kJ)\times(1\ kcal/4.184\ kJ)\approx3155\ kcal$

Answer:

a. $2.372228\times10^{6}\ J$
b. 681 Cal
c. 0.968504 kJ
d. 3155 kcal