If SR + O2(g) `->` SO2(g);` Delta` H = -71.1 kcal....(i)
SM + O2(g) `->` SO2(g); `Delta` H = 71.7 kcal......(ii)
The heat of transition for SM `->` SR is .........
-1.2
-0.6
+1.2
+0.6
ca anyone help me shouldnt it be 71.7+71.1