# 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)

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

$m = \text{2.5 kg}$
$c = \text{2.60 kJ·°C"^"-1""kg"^"-1}$
ΔT = T_"f" - T_"i" = "75 °C - 15 °C = 60 °C"
$q = \text{2.5" color(red)(cancel(color(black)("kg"))) × "2.60 kJ"·color(red)(cancel(color(black)("°C"^"-1"·"kg"^"-1"))) × "60" color(red)(cancel(color(black)("°C"))) = "390 kJ}$