Question

Question #93e81

Answer 1

It will take 24 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 = "1 kg"`
`c = "664 J·K"^"-1""kg"^"-1"`
`ΔT = T_"f" - T_"i" = "122 °C - 86 °C = 36 °C = 36 K"`

∴ `q = 1 color(red)(cancel(color(black)("kg"))) × "664 J"·color(red)(cancel(color(black)("K"^"-1"·"kg"^"-1"))) × 36 color(red)(cancel(color(black)("K"))) = "23 900 J" = "24 kJ"`