function work12_1



function dydz = equations(z, y)
R = 8.314;
cT = y(1);
cH = y(2);
cB = y(3);
cM = y(4);
T = y(5);
k = 3.5e9.*exp(-50900./R./T);
rT = k.*cT.*cH.^0.5/3600;
u =