How much heat does it take to raise the temperature of 2.5 kg of plastic from 15°C to 75°C?

The specific heat of plastic is 2.60 kJ/(kg•°C)

1 Answer
Oct 18, 2016

It will take 390 kJ of heat.

Explanation:

The energy #q# required to heat an object is given by the formula

#color(blue)(bar(ul(|color(white)(a/a)q = mcΔTcolor(white)(a/a)|)))" "#

where

#m# is the mass
#c# is the specific heat capacity
#ΔT# is the change in temperature

In your problem,

#m = "2.5 kg"#
#c = "2.60 kJ·°C"^"-1""kg"^"-1"#
#ΔT = T_"f" - T_"i" = "75 °C - 15 °C = 60 °C"#

#q = "2.5" color(red)(cancel(color(black)("kg"))) × "2.60 kJ"·color(red)(cancel(color(black)("°C"^"-1"·"kg"^"-1"))) × "60" color(red)(cancel(color(black)("°C"))) = "390 kJ"#