PbCl2 is insoluble in cold water but soluble in hot water
Aldehydes are usually more reactive<span> toward nucleophilic substitutions </span>than<span> ketones because of both steric and electronic effects. In aldehydes, the relatively small hydrogen atom is attached to one side of the carbonyl group, while a larger R group is affixed to the other side.</span>
Mos commonly 2 elements combine.
examples: H2, O2
Ninety-nine percent of all matter that can be observed in the universe exists as plasmas