Week 10 Discussion Notes (2E,2I,2K)

[Chem_Mod]

Dear all,

Attached please find the worksheet answer key and discussion notes.

Good luck on your finals! ٩(๑>◡<๑)۶

Best,
Joyce

[Meachelle_Lum_1I]

Hi, does anyone know why delta H was 300 and not -300 when calculating the reverse activation energy? Didn't they give it as -300, and it's an exothermic reaction so deltaH should be negative?

[Tony Ong 3K]

Thank you so much this quarter Joyce!!!
Definitely the greatest TA to have walked this Earth.

[Chem_Mod]

Hi, does anyone know why delta H was 300 and not -300 when calculating the reverse activation energy? Didn't they give it as -300, and it's an exothermic reaction so deltaH should be negative?

For the reverse reaction, new delta H = - delta H. The forward reaction is exothermic and delta H = -300, then the reverse reaction is endothermic and delta H = +300.

Hope this helps.

[Samantha Silva 1F]

Thank you for the worksheet!

[Kobe_Wright]

Thank You!

[Kobe_Wright]

Hi, does anyone know why delta H was 300 and not -300 when calculating the reverse activation energy? Didn't they give it as -300, and it's an exothermic reaction so deltaH should be negative?

Going in reverse, you'd switch the sign around. You're doing the reaction backwards.