Consider a particular reaction that has an activation energy of 450 kj and an enthalpy of reaction of +250 kj. when a catalyst is added to the reaction, the new activation energy is measured to be 400 kj.
the reaction is (endothermic or exothermic)* . the enthalpy of reaction for the catalyzed reaction is (150, 250, 350, 650, 850)* kj.

*there are two answers needed to be answered^^
the endo/exo and the number one

what are the statements

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2