Cr2O3+H2O= CaO+H2O= Al+H2O= CrO3+H2O= Si+H2O= Zn+H2O= Al2O3+H2O= BaO+H2O= Li+H2O= CO2+H2O= C+H2O= Ni+H2O=

Here are the reactions for each of the compounds with water (H2O), where applicable: 1. **Cr2O3 + H2O →** This reaction does not typically occur under standard conditions. Chromium(III) oxide is very stable and does not readily react with water. 2. **CaO + H2O → Ca(OH)2** Calcium oxide (lime) reacts with water to form calcium hydroxide (slaked lime). 3. **Al + H2O →** Under normal conditions, aluminum does not react with water due to an oxide layer. However, at elevated temperatures or in the presence of steam: \[\text{2Al + 6H2O} \rightarrow \text{2Al(OH)3 + 3H2}\] 4. **CrO3 + H2O → H2CrO4** Chromium trioxide reacts with water to form chromic acid (H2CrO4). 5. **Si + H2O →** Silicon does not react with water under normal conditions. 6. **Zn + H2O →** Zinc reacts slowly with water. More commonly, in the presence of steam: \[\text{Zn + H2O (g) → ZnO + H2}\] 7. **Al2O3 + H2O → Al(OH)3** Aluminum oxide reacts with water to form aluminum hydroxide. 8. **BaO + H2O → Ba(OH)2** Barium oxide reacts with water to form barium hydroxide. 9. **Li + H2O →** Lithium reacts vigorously with water: \[\text{2Li + 2H2O → 2LiOH + H2}\] 10. **CO2 + H2O → H2CO3** Carbon dioxide reacts with water to form carbonic acid (H2CO3). 11. **C + H2O →** Carbon reacts with steam at high temperatures to produce hydrogen gas and carbon monoxide: \[\text{C + H2O (g) → CO + H2}\] 12. **Ni + H2O →** Nickel does not react with water under normal conditions. Please note that the reactivity and outcomes can depend on specific conditions such as temperature and pressure.