Compounds of boron and hydrogen are remarkable for their unusual bonding and also for their reactivity. With the more reactive halogens, for example, diborane (B2H6) forms trihalides even at low temperatures:
B2H6(g)+6Cl2(g)→2BCl3(g)+6HCl(g) ΔHrxn=?755.4kJ
How much heat is released per kilogram of diborane that reacts?