set up a experiment

I will do this tmr ...so I think it may be like this

　　　　　　　　　　 　(p1)
Ca ( s) +C (graphite) (s) + 3/2 O2 (g)---------------＞CaCO3 (s)
! (p5) *************** ! (p4)********************************* /
! +2HCI ************ ! ******* ***************** ********** /+2HCI
! ********************* ! ******* ***************** **********/
V ********************V ******* ***************** ********/(p2)
CaCI2(aq)+H2(g) + CO2+1/2 O2(g) ******* **********/
****************** ! ******* ***************** ***********/
****************** ! (p3) ******* ********************* /
***************** V ******* **************************/
CaCI2(aq)+CO2+H2O(l) 　　　　　　　<---- /

Enthalphy change of formation of calcium carbonate
(p1)=(p5)+(p4)+(p3)-(p2)



!!!e.g. (p1) = PATH 1.
the position of the 2HCl ...you can put it within the arrow...or put it on each side of the (p1)
such as below:

　　　　　　　　　　 　(p1)
2HCl(aq)+ Ca ( s) +C (graphite) (s) + 3/2 O2 (g)---------------> CaCO3 (s) +2HCl(aq)


..I hope it is right and it can help u la~~~
regardless of the *****..just for keeping the space ,,,otherwise,every word would turn out to be very messy...

your science teacher will know.kk