Answer:
This is an oxidation-reduction (redox) reaction:
2 HI + 2 e- → 2 H0 (reduction)
Fe0 - 2 e- → FeII (oxidation)
HCl is an oxidizing agent, Fe is a reducing agent.
Reactants:
Fe
Names: Iron source: wikidata, accessed: 2019-09-07, Fe source: wikidata, accessed: 2019-09-07, Element 26 source: wikidata, accessed: 2019-09-07... show more
HCl – Chlorane source: wikipedia, accessed: 2019-09-27, Hydrogen chloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
Other names: Hydrochloric acid sourc2 2019-09-27source: NIOSH NPG, accessed: 2019-09-02, M source: wikipedia, accessed: 2019-09-27, Uriatic acid source: wikipedia, accessed: 2019-09-27... show more
Appearance: Colorless, transparent liquid, fumes in air if concentrated source: wikipedia, accessed: 2019-09-27; Colorless gas source: wikipedia, accessed: 2019-09-27; Colourless compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed: 2019-09-02
Products:
FeCl2 – Iron(II) chloride source: : 2019-09-27source: ICSC, accessed: 2019-09-04, Iron dichloride source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04
Other names: Ferrous chloride source 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Rokühnite source: wikipedia, accessed: 2019-09-27, [FeCl3] source: wikidata, accessed: 2019-09-02, FeCl3 source: wikidata, accessed: 2019-09-02
Appearance: Tan solid (anhydrous) | Pale green solid (di-tetrahydrate) source: wikipedia, accessed: 2019-09-27; White-to-light-green hygroscopic crystals source: ICSC, accessed: 2019-09-04
H2
Names: Dihydrogen source 2019-09-07, Hydrogen source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-07, H2 source: wikidata, accessed: 2019-09-07... show more
Appearance: Odourless colourless compressed gas source: ICSC, accessed: 2019-09-04
Hope this helps