Na + H2SO4 → NaSO4 + H2
This is an oxidation-reduction (redox) reaction:
Na0 - 1 e- → NaI (oxidation)
SVI - 1 e- → SVII (oxidation)
2 HI + 2 e- → 2 H0 (reduction)
Na is a reducing agent, H2SO4 is a reducing agent, H2SO4 is an oxidizing agent.
Warning: Unknown compound 'NaSO4'