Question

Determine the value for the following reaction.

2HI(g) + 2.4 kcal → H2(g) + l2(g)
ΔH = _____
2.4 kcal
-2.4 kcal
0.0024 kcal
-0.0024 kcal

Answer 1

Answer: 2.4 kcal

Step-by-step explanation:

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and
`\Delta H` for the reaction comes out to be positive.

For the given reaction:

`2HI+2.4kcal\rightarrow H_2(g)+I_2(g)`

Enthalpy change is the net heat absorbed or released during a chemical reaction.

As heat is added to reactants, energy is being absorbed and thus enthalpy for the reaction will be positive and the value will be +2.4 kcal.

Answer 2

ΔH = + 2.4 kcal

Step-by-step explanation:

2HI(g) + 2.4 kcal ⇌ H₂(g) + I₂(g)

Energy is on the left-hand side of the equation, so it is being absorbed by the system.

The thermodynamic convention is that energy going into a system is positive. Thus,

ΔH = + 2.4 kcal