Question

What are the number of joules required to raise the temperature of 1000 g of ethyl alcohol by 15 degrees celcius?

Answer 1

`691560` joules

Explanation:

The specific heat formula is:

`q=mcDeltaT`

where:

• `q` is the heat energy supplied in joules

• `m` is the mass of the substance

• `c` is the specific heat capacity of the substance, for ethyl alcohol is `(2.4 \ "J")/("g K")` (source: http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/sphtt.html)

• `DeltaT` is the change in temperature

First let's convert celsius into kelvin. Know that, `"K"=""^@"C"+273.15`.

`:.15^@"C"=288.15 \ "K"`

So, the heat energy needed is:

`q=1000color(red)cancelcolor(black)"g"*(2.4 \ "J")/(color(red)cancelcolor(black)"g"color(red)cancelcolor(black)"K")*288.15color(red)cancelcolor(black)"K"`

`=691560 \ "J"`