## owlet one year ago Enthalpy I need step-by-step guidance please and thank you in advance. Question Below:

1. owlet

2. owlet

@Jhannybean

3. Jhannybean

$\Delta H = \sum {n\cdot \text{products} -\sum m \cdot \text{reactants}}$ m and n are coefficients of the reactants and products,respectively.

4. Jhannybean

So you're given $$\Delta H = -89 \frac{kJ}{mol}$$

5. owlet

yeah i think I manage it now, just to make sure Hf for I2 is zero right?

6. owlet

**can

7. Jhannybean

Yes, all diatomics and elements

8. owlet

thanks!

9. Jhannybean

$-89 \frac{kJ}{mol} = -840\frac{kJ}{mol} +2\text{IF} -\left( -942 \frac{kJ}{mol}\right)$

10. owlet

that's what i did and i got -94.5 kJ

11. Jhannybean

- 89 = 2x - 840 + 942 -89 = 2x +102 -89 - 102 = 2x -191 = 2x x = -191/2 = -95.5