Describe the heat involved if you touch a flask containing an on-going endothermic reaction

Does the temperature affect the solubility of sugar and salt in water? if it does tell me like different temperatures with different solubilities so i can sketch down a graph

Bohr's model could only explain the spectra of which type of atoms? single atoms with one electron single atoms with more than one electron bonded atoms with one electron bonded atoms with more than one electron

How many neutrons does a atom of cobalt have?