**7. Discussions on analytical results using various metallic/non-metallic nanoparticles**

**Table 2** shows the ratios of density to conductivity of various metallic/nonmetallic nanoparticles and density 997.1 and conductivity 0.613 of water is used.

It is observed that ratio of density to conductivity is accountable for hastening the onset of convection in the system. The ratio is more for non-metals than metals establishes the lesser stability of non-metallic nanoparticles than metals. Alumina is


**Table 2.**

*Ratios of density to conductivity of metallic and non-metallic nanoparticles.*

most stable and titanium oxide is least stable among the nanoparticles under consideration. Density is found to be more influential than conductivity towards deciding the onset of convection in the layer.

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