contestada

A chemical reaction gives off 1,500 kJ of heat energy. About how many calories is this? (1 calorie = 4.18 Joules)

Respuesta :

Moly42
First you need to convert kiloJoules to Joules

1 kJ is 1000 J

1500kJ *1000J == 1500000 J
Then 1500000J * 1Cal/4.18 J == 358851.6746 calories

Answer : The heat energy in calorie is [tex]3.59\times 10^5\text{ Calorie}[/tex]

Explanation :

As we are given the conversion for heat energy.

[tex]1\text{ Calorie}=4.18\text{ Joules}[/tex]

or,

[tex]1\text{ Joules}=\frac{1}{4.18}\text{ Calorie}[/tex]

As we are given that:

Heat energy in kJ = 1500 kJ = 1500000 J

conversion used : (1 kJ = 1000 J)

Now we have to determine the heat energy in calorie.

As, [tex]1\text{ Joules}=\frac{1}{4.18}\text{ Calorie}[/tex]

So, [tex]1500000\text{ Joules}=\frac{1500000\text{ Joules}}{4.18\text{ Joules}}\text{ Calorie}=3.59\times 10^5\text{ Calorie}[/tex]

Therefore, the heat energy in calorie is [tex]3.59\times 10^5\text{ Calorie}[/tex]