function hx = HtRxn(T)
Hx0 = 80.77e3; % kJ/kgmol
Tk = T/1000;
Tk0 = (25+273.15)/1000;
% acetone
HA = (6.8132e-3*Tk+0.2786/2*Tk^2-0.15628/3*Tk^3+0.03476/4*Tk^4 ...
    - (6.8132e-3*Tk0+0.2786/2*Tk0^2-0.15628/3*Tk0^3+0.03476/4*Tk0^4))*1000;
% ketene
HK = 18.909*Tk + 143.56/2*Tk^2 - 130.23/3*Tk^3 + 66.526/4*Tk^4 - 14.112/5*Tk^5 ...
    - (18.909*Tk0 + 143.56/2*Tk0^2 - 130.23/3*Tk0^3 + 66.526/4*Tk0^4 - 14.112/5*Tk0^5);
% methane
HM = -0.703028*Tk + 108.4773/2*Tk^2 - 42.52157/3*Tk^3 + 5.862788/4*Tk^4 - 0.678565/Tk ...
    - (-0.703028*Tk0 + 108.4773/2*Tk0^2 - 42.52157/3*Tk0^3 + 5.862788/4*Tk0^4 - 0.678565/Tk0);
hx = Hx0 + ( - HA + HK + HM )*1000;
