What are the sings of the entropy change (+ or - ) in the following :
I: A liquid crystallise into a solid
II: Temperature of a crystalline solid is raised from 0 k to 115K
III:$2{\mathrm{NaHCO}}_{3\left(s\right)}\to {\mathrm{Na}}_2{\mathrm{CO}}_{3\left(s\right)}+{\mathrm{CO}}_2\left(g\right)+{\mathrm{H}}_2{\mathrm{O}}_{\left(g\right)}$
IV:${\mathrm{H}}_{2\left(\mathrm{g}\right)}\to 2{\mathrm{H}}_{\left(\mathrm{g}\right)}$