Reaction enthalpy for an exothermic reaction is negative- why?

Changeof enthalpy in exothermic reaction

What are exothermic reactions?

Enthalpy Change for exothermic process—

Why is the sign of DeltaH negative for an exothermic reaction and why is it positive for an endothermic reaction?

How does the spontaneity of an exothermic reaction depend on temperature when (i) DeltaS gt0 and (ii) DeltaS lt0 ?

Which of the following is an exothermic reaction?

If DeltaG for a reaction is negative, the change is

At 25^(@)C , the standard reaction enthalpy for the reaction, 2C(graphite, s) +O_(2)(g)to2CO(g) is -221.0kJ. Does this enthalpy change indicate the standard enthalpy of formation of CO(g) ? If not, then what would be the value of the enthalpy of formation of CO(g) at 25^(@)C ?

At 25^(@) C, is the standard reaction enthalpy for the reaction 2H(g) +O(g)toH_(2)O(l) the same as the standard enthalpy of formation of H_(2)O(l) ?

At 25^(@)C and 1 atm, the standard reaction enthalpy for the reaction C(graphite, s) +O_(2)(g)toCO_(2)(g) is the _____ of CO_(2)(g) .