Respuesta :

kenmyna
The moles of Ba(OH)2 that is  required  to react  with 117 HBr is calculated as  below

find the moles of HBr used
mass/  molar mass = 117 g/ 80.9 g/mol = 1.446  moles

write the reacting equation

Ba(OH)2 +  2 HBr =  BaBr2 + 2 H2O

by use of mole ratio of Ba(OH)2 : HBr  which is 1:2 the moles of Ba(OH)2 is therefore
= 1.446 moles x1/2 = 0.723  moles  of Ba(OH)2