please assist me with this themochemistry question

Question

Given the following data

CaCO3 (s)>>>>>>CaO (s) + CO2(g) (g) Delta H = -178.1 kj
C (s) + O2>>>>>>CO2 (g) Delta H = -393.5 kj

Calculate enthalpy in kj of the following reaction

CaCO3 (s)>>>>>>>>>CaO (s) + C (s) + O2 (g)

a) 215.4
b) 571.6
c) -215.4
d) -571.6
e) 178.

Answer 1

Add equation 1 to the reverse of equation 2 and you will obtain the reaction you want. Change the sign of delta H for equation 2 (since it is reversed) and add it to delta H for equation 1 to obtain delta H for the desired reaction.

Answer 2

htryh