3A chemical reaction produces 653 550 kJ of energy as heat in 142.3 min. What is the rate of energy transfer in kilojoules per minute.?

1 Answer
Jul 22, 2016

#"4593 kJ min"^(-1)#


Notice that the problem provides you with

  • the total amount of energy released by the reaction
  • the total time needed for this energy to be released

Your goal here will be to use this information to find the rate of energy transfer, which is simply the amount of energy produced per minute by the reaction, assuming of course that the heat is released at a constant rate.

Essentially, you must figure out how much heat is given off in one minute by using the fact that you know how much heat is being given off in #"142.3# minutes.

Use the information given to you by the problem as a conversion factor to find

#1 color(red)(cancel(color(black)("minute"))) * "653,550 kJ"/(142.3 color(red)(cancel(color(black)("min")))) = "4592.76 kJ"#

Now, because this is how much heat is given off in #1# minute, you can say that the rate of energy transfer is

#"rate of energy transfer" = color(green)(|bar(ul(color(white)(a/a)color(black)("4593 kJ min"^(-1))color(white)(a/a)|)))#

The answer is rounded to four sig figs, the number of sig figs you have for the total time of the reaction.