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We know when lithium is burnt in air, it forms lithium nitride and lithium oxide. I am wondering if this applies to aluminium (other metals) also?

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  • $\begingroup$ Magnesium also forms the nitride as well as the oxide when burning in air. $\endgroup$ – Oscar Lanzi Dec 26 '19 at 20:39
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According to the paper by Gromov and Vereshchagin [1], it is indeed formed when burning aluminium, but you could have predicted this simply by considering the standard enthalpy of formation of aluminium oxide $\Delta_\mathrm{f}H^\circ (\ce{Al2O3}) = \pu{−1675.7 kJ/mol}$ which will be liberated upon ignition and this energy helps in breaking the strong nitrogen-nitrogen triple bond (bond energy is $\pu{−945 kJ/mol})$ and finally this would form aluminium nitride, which also produces some energy (standard enthalpy of formation is $\pu{−318 kJ/mol}),$ but the combustion here is not a simple one it requires high temperature as mentioned in the paper, I think this is to sublimate $\ce{Al2O}$ which will react with nitrogen and give rise to aluminium nitride.

As HYDR0GEN stated, this combustion isn't simple like throwing a match on aluminium sheet, it needs high temperature. According to the work by Trunov et al. [2, p. 38], as the size of aluminium particles decrease the needed temperature for combustion decreases and that's why researchers who wrote the paper used superfine aluminium powder:

enter image description here
Figure 5. Experimentally determined temperatures of aluminum ignition as a function of the used sample size.

References

  1. Gromov, A.; Vereshchagin, V. Study of Aluminum Nitride Formation by Superfine Aluminum Powder Combustion in Air. Journal of the European Ceramic Society 2004, 24 (9), 2879–2884. DOI: 10.1016/j.jeurceramsoc.2003.09.020. (PDF)
  2. Trunov, M. A.; Schoenitz, M.; Dreizin, E. L. Ignition of Aluminum Powders Under Different Experimental Conditions. Propellants, Explosives, Pyrotechnics 2005, 30 (1), 36–43. DOI: 10.1002/prep.200400083.
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  • $\begingroup$ When citing third-party resources, make sure to provide a complete human-readable reference and not just "this link" to make your post robust against link rot. Also, always cite the original publication, not a reproduced rip-off of a questionable quality where there is typo in the axis name ("Diamter") and illiterate numbers formatting. I took a liberty to replace the illustration with with the one from original paper. $\endgroup$ – andselisk Dec 27 '19 at 11:48
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    $\begingroup$ @andselisk thanks for help, it's my first answer $\endgroup$ – mohamed Dec 27 '19 at 11:57
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When the aluminum [powder] is ignited, it will cause a reaction between the aluminum and oxygen in the atmosphere. The required temperature for the aluminum oxide to be formed is almost 3000+ °C.

$$\ce{4 Al + 3 O2 -> 2 Al2O3}$$

In addition, aluminum nitride can't be formed when the aluminum powder is ignited in atmosphere, because the aluminum nitride starts to decompose into aluminum and $\ce{N2}$ at a high temperature under atmospheric pressure.

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    $\begingroup$ Aluminium needs high temperature to be ignited but that's why the researchers who wrote the paper used ultra fine powder of aluminium to be ignited easily . See this link :researchgate.net/figure/… $\endgroup$ – mohamed Dec 27 '19 at 9:08

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