What is formed when hydrobromic acid, hbr, and calcium hydroxide, ca(oh)2, are combined?

This is an acid – base reaction and this always result a salt and water in a neutralization reaction. 

The salt that is formed will be calcium bromide (calcium is located in group 2 so calcium bromide has a formula of CaBr2) 

so essentially we got:

HBr + Ca(OH)2 > CaBr2 + H2O

balancing the elements: 

2HBr(aq) + Ca(OH)2(aq) > CaBr2(aq) + 2H2O(l)

personal, she chose to do it.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.