Measurements show that unknown compound X has the following composition: element mass %
carbon 62.6%
hydrogen 4.20%
oxygen 33.4%
Write the empirical chemical formula of X.

An aqueous solution of calcium hydroxide is standardized by titration with a 0.120 m solution of hydrobromic acid. if 16.5 ml of base are required to neutralize 27.5 ml of the acid, what is the molarity of the calcium hydroxide solution?

In an exothermic reaction the bonding energy of the product is: less than the reactants same as the reactants greater than the reactants dependent upon the presence of a catalyst

Stage in which a star’s outer layers have started to cool and grow outward?