# Question #fae70

##### 1 Answer

#### Explanation:

You can switch things up a little and solve by converting the specific heat of copper from *joules per gram Celsius* to *kilojoules per kilogram Celsius* by using the two conversion factors

#"1 kJ" = 10^3color(white)(.)"J" " "# and#" " "1 kg" = 10^3color(white)(.)"g"#

You will end up with

#0.385 color(white)(.)color(red)(cancel(color(black)("J")))/(1color(red)(cancel(color(black)("g"))) * 1^@"C") * "1 kJ"/(10^3color(red)(cancel(color(black)("J")))) * (10^3color(red)(cancel(color(black)("g"))))/"1 kg" = "0.385 kJ kg"^(-1)""^@"C"^(-1)#

So, you know that in order to increase the temperature of

You can use the specific heat of copper to figure out the amount of heat needed to increase the temperature of

#6.62 color(red)(cancel(color(black)("kg"))) * "0.385 kJ"/(1color(red)(cancel(color(black)("kg"))) * 1^@"C") = "2.549 kJ"""^@"C"^(-1)#

This means that in order to increase the temperature of

Finally, you can use this information to determine the amount of heat needed to increase the temperature of

#334.3^@"C" - 22.5^@"C" = 311.8^@"C"#

You should get

#311.8color(red)(cancel(color(black)(""^@"C"))) * overbrace("2.549 kJ"/(1color(red)(cancel(color(black)(""^@"C")))))^(color(blue)("for 6.62 kg of copper")) = color(darkgreen)(ul(color(black)("795 kJ")))#

The answer is rounded to three **sig figs**.