$\mathrm{I}) 6{\mathrm{CO}}_{2_{\left(\mathrm{g}\right)}}+6{\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{l}\right)}\underset{\mathrm{Chlorophyll}}{\overset{\mathrm{Sunlight}}{\to }}\underset{\mathrm{Glucose}}{{\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_{6\left(\mathrm{s}\right)}}+6{\mathrm{O}}_{2\left(\mathrm{g}\right)}$

$\mathrm{II}) 2\mathrm{AgBr}\stackrel{\mathrm{hv}}{\to }2\mathrm{Ag}+{\mathrm{Br}}_2$

The above reactions are examples for _______