Breaking water molecule
 

Hi, While a mere 1.3 volts can break bonds in a water molecule, I have been reading that it takes 2000-3000 degrees celsius to break same bonds thermally. Such high temperatures intuitively appear to be very high energy compared to 1.3 volts. Why does it take such high temperatures? How exactly can a small voltage like 1.3V works? Any theoretical/mathematical explanation for this?
Thanks