[填空题]
When two moles of hydrogen dw0 +ia*e3q nmscp i29and one mole otw l)r * c7hmln:3,8v1qypfv-qplz 0ef oxygen react to form two moles of water, the energy released is 484 kJ. How much does the mass nl vmq hr l,l7cv3:pwpy01) zq8-ft *eof the elements decrease in this reaction?
$\Delta m$ = $\times 10^{-12} \, \text{kg}$
What % of the total original mass of the system does this mass change represent? $ \times 10^{-8}\%$
