which equation is a decomposition reaction?\no li2co3 → li2o + co2\no zn + hcl → zncl2 + h2\no na2o + co2 →…

Brief Explanations:

A decomposition reaction is one in which a single compound breaks down into two or more simpler substances. In the equation $\mathrm{Li_2CO_3}\rightarrow\mathrm{Li_2O}+\mathrm{CO_2}$, lithium carbonate ($\mathrm{Li_2CO_3}$) breaks down into lithium oxide ($\mathrm{Li_2O}$) and carbon - dioxide ($\mathrm{CO_2}$). The second equation is a single - displacement reaction, the third is a combination reaction, and the fourth is a combustion reaction.

Answer:

$\mathrm{Li_2CO_3}\rightarrow\mathrm{Li_2O}+\mathrm{CO_2}$