Some chemicals are very caustic.
Your supplier or the manufacturer can assist you with that information. For low temp developing and underexposed negs. Hydroquinone 14 grams Sodium Hydroxide 8.8 grams Potassium Bromide 8.8 grams Cold Water to make 1 liter Dissolve the sodium hydroxide in a small amount cold water. Then pour this into the mixture, after the hydroquinone with rapid agitation. If you pour sodium hydroxide into hot water, an explosive reaction can occur which can cause burning.