Carter

Here is the question:

The enthalpy change for the oxidation of styrene, C8H8, is measured by calorimetry.

C8H8(l) + 10 O2(g) --> 8 CO2(g) + 4 H2O(l)

The standard reaction enthalpy is -4,395.0 kJ / mol-rxn.

Use this value, along with the standard enthalpies of formation of CO2 (-393.509) and H2O (-241.83), to calculate the enthalpy of formation of styrene in kJ/mol.

What I'm trying to do:

Since the standard reaction enthalpy is equal to the sum of the standard enthalpies of formation of the products minus the sum of the standard enthalpies of formation of the reactants, I have:

-4,395.0 kJ/mol-rxn = [ 8(-393.509 kJ/molCarbon) + 4(-241.83 kJ/molWater)] -- [ 10(0 kJ/molO2) + 1(x kJ/molC8H8)]

Simplified to: -4,395 = -4,115.392 - x then x comes out to be 279.608 kJ/mol.

However the correct answer is 103.6 kJ/mol. 10 points to whoever can correct where I went wrong. Thank you!

I am a sophomore in high school, and I sign up for next year's classes soon. I think that I am going to double up on science next year and senior year, and between these two years take AP Chem, AP Phys, AP Bio, and Anatomy. I think it would be best if I take Chemistry and Physics together, probably next year, and then Biology and Anatomy senior year, because I feel like Chem and Phys would overlap a little, and Anatomy and Bio would complement each other well. Does anyone have any input on if there are better ways to combine them?

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Medicī Romanī addunt medicinam- Roman doctors give medicine.

Medicus est scitus.- The doctor is smart.

Medicī in Italiā et Africa adhuc hodie medicinam utiunt.- Doctors in Italy and Africa still use medicine today.

Did I translate all of these English sentences to Latin correctly? Any grammar or vocabulary errors that you notice? Or are there are any better words I could use to say what i mean?

Medicī Romanī addunt medicinam- Roman doctors give medicine.

Medicus est scitus.- The doctor is smart.

Medicī in Italiā et Africa adhuc hodie medicinam utiunt.- Doctors in Italy and Africa still use medicine today.

Did I translate all of these English sentences to Latin correctly? Any grammar or vocabulary errors that you notice?

The Wal-Mart near me is a 24 hour store and the games are released on October 12th(this Saturday.) So will Wal-Mart have them out right at midnight or not until the morning?

The Wal-Mart near me is a 24 hour store and the games are released on October 12th(this Saturday.) So will Wal-Mart have them out right at midnight or not until the morning?

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Okay so im 15 and I've had a twitter for awhile and I swear and mildly talk about sexual stuff in my tweets and they told me they found it but I have friends over so they haven't talked to me much yet. I probably have until tomorrow morning at the latest. Help.

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