Chemistry

Question

Ethyl alcohol has a heat of vaporization of 850. J/g. What mass of ethyl alcohol can be boiled using 15000 J of energy?

2 Answer

  • The amount of heat, H, needed to boil off certain mass, m, of the substance is given by the equation,
                                    H = mHv
    where Hv is the heat of vaporization. Manipulating the equation, the mass is calculated by,
                                    m = H/Hv
    Substituting the known values,
                                    m = 15000 J/(850 J/g) = 17.65 g
    Thus, the mass of ethyl alcohol is approximately 17.65 g. 
  • Answer:

    17.64 grams of ethyl alcohol can be boiled using 15000 J of energy.

    Explanation:

    Heat of vaporization of ethyl alcohol = [tex]=\Delta H_{vap}850 J/g[/tex]

    Mass of ethyl alcohol boiled using 15000 Joule of energy = m

    Q = 15000 J

    [tex]Q=m\times \Delta H_{vap}[/tex]

    [tex]15000 J=m\times 850 J/g[/tex]

    m = 17.64 g

    17.64 grams of ethyl alcohol can be boiled using 15000 J of energy.

NEWS TODAY