Question

The heat combustion of acetylene, C2H2(g), at 25°C, is –1299 kJ/mol. At this temperature, ΔHvalues for CO2(g) and H2O(l) are –393 and –286 kJ/mol, respectively. Calculate ΔHfor acetylene. (Practicing)

Answer 1

http://www2.tku.edu.tw/~tscx/2009chinese/other/tb06.pdf

Answer 2

C2H2 (g) + 5/2 O2 (g) --> 2 CO2 (g) + H2O (g) deltaH = -1299 kJ/mol

Answer 3

You need to know the heat of combustion for:
C + O2 --> CO2 [about - 400 kJ/mol]
H2 + 1/2 O2 --> H2O [about -250 kJ/mol]

Answer 4

Delta H = Sum Products - Sum of the reactant

Answer 5

look at apendix2

Answer 6

and what do I look at ?

Answer 7

C2H2

Answer 8

yeah but

Answer 9

We must break the door -.- not evade it

Answer 10

yea but his is just part because it says per mole not just delta H

Answer 11

that is per mole...

Answer 12

kJ/mole

Answer 13

C2H2 + 2.5O2 ===> 2CO2 + H2O

Answer 14

\[\Delta H = H (products) - H (reactants)\]

Answer 15

ok so it is 227kj/mol so how would we solve it without the table?

Answer 16

-1299 = [2(-393)+(-286)]-[C2H2 + (0)]

Answer 17

oh ok i got it

Answer 18

add both negative you get -1072 and then -(-1299) and you get =227

Answer 19

crap it got deleted lol

Answer 20

For a particular process q = 20 kJ and w = 15 kJ. Which of the following statements is true?

Answer 21

this is the next Q

Answer 22

yes

Answer 23

For a particular process q = 20 kJ and w = 15 kJ. Which of the following statements is true?
a.
Heat flows from the system to the surroundings.
b.
None of the above are true.
c.
All of the above are true.
d.
The system does work on the surroundings.
e.
ΔE = 35 kJ.

Answer 24

im looking for it

Answer 25

U=q+w

Answer 26

20+15 = 35kJ

Answer 27

that easy?

Answer 28

yes, because we know the subjects >.>

Answer 29

that's how easy is chapter 4 but we have no idea of it lol

Answer 30

for real

Answer 31

so its E.

Answer 32

I believe so