Q.List two major industrial uses each of aluminium metal and of $\text{LiAlH}_4$, and explain briefly why aluminium's natural oxide layer makes the metal appear unreactive despite being high in the reactivity series.

[!TLDR] Aluminium is used in aircraft/vehicle bodies and electrical cabling/packaging foil; LiAlH4 is used to reduce carbonyl compounds and other functional groups in synthesis. Aluminium's natural oxide film passivates the metal against everyday attack. [!ANSWER] Aluminium: aircraft/vehicle structural alloys and electrical transmission cabling (also packaging foil, cookware). LiAlH4: reduction of aldehydes/ketones/esters/carboxylic acids and other functional groups in organic syn …

Aluminium metal is used extensively wherever a combination of light weight, good strength (especially as alloys), corrosion resistance and good electrical/thermal conductivity is valuable: two major uses are in aircraft and vehicle body/structural components (its low density relative to strength makes it far preferable to steel for weight-sensitive applications) and in electrical transmission cabling (it is a good conductor and, being far lighter than copper for a given conductance, is widely used for overhead power lines); it is also widely used for packaging foil and cooking utensils. $\text{LiAlH}_4$ is one of the most important reducing agents in synthetic organic chemistry, used to reduce a wide range of functional groups by hydride delivery — most importantly aldehydes, ketones, esters and carboxylic acids to the corresponding alcohols, and also nitriles and other reducible groups to amines — making it a standard reagent across pharmaceutical and fine-chemical synthesis. Despite aluminium sitting reasonably high in the reactivity series (more reactive than iron, for instance), it appears deceptively unreactive in ordinary use because a very thin, extremely tough and self-healing layer of aluminium oxide, $\text{Al}_2\text{O}_3$, forms almost instantaneously on any freshly exposed aluminium surface on contact with air. This oxide layer adheres tightly to the underlying metal and effectively seals it off from further attack by air or water; if the layer …

Name two representative industrial uses each for aluminium metal and for LiAlH4, then explain the passivating self-healing oxide layer that reconciles alumini …

Confusing uses of aluminium metal with uses of Al2O3 (a separate earlier question); omitting the 'self-healing' aspect of the oxide layer, which is what specific …