مقدار گرمای آزاد شده از كدام واكنش كمتر است؟
1 )
${{C}_{2}}{{H}_{4}}(g)+3{{O}_{2}}(g)\to 2C{{O}_{2}}(g)+2{{H}_{2}}O(g)$
2 )
${{C}_{2}}{{H}_{4}}(l)+3{{O}_{2}}(g)\to 2C{{O}_{2}}(g)+2{{H}_{2}}O(l)$
3 )
${{C}_{2}}{{H}_{4}}(g)+3{{O}_{2}}(g)\to 2C{{O}_{2}}(g)+2{{H}_{2}}O(l)$
${{C}_{2}}{{H}_{4}}(l)+3{{O}_{2}}(g)\to 2C{{O}_{2}}(g)+2{{H}_{2}}O(g)$