Question

Which of the following statements concerning the reaction shown below are true?

P4 (s) + 3O2 (g) → P4O6 (s) ∆H = -1640 kJ

I. heat is absorbed
II. heat is released
III. rxn is exothermic
IV. rxn is endothermic
V. products have higher enthalpy content than reactants
VI. reactants have higher enthalpy content than products


A. I, III, and V
B. II, III, and V
C. II, III, and VI
D. I and III

Answer 1

@superhelp101

Answer 2

ohh i am so sorry @MacAttack123315 i am no good a chem. but have maybe @paki help you!

Answer 3

Okay haha :) yeah this is like the last one @paki, but just a little bit different

Answer 4

again rain... lol

Answer 5

hahahahhahahahah @MacAttack123315 give the medal to paki :)

Answer 6

Hahaha what do you mean?

Answer 7

nah it is fine ;)

Answer 8

let me make the calculation equal.... 1+1+1.... rite

Answer 9

...?

Answer 10

the medals ?

Answer 11

yeah

Answer 12

it is a thunderstorm :)

Answer 13

so @paki do you know how to do this one??

Answer 14

confused here...

Answer 15

@Preetha @PRAETORIAN.10 @Purplerainbowcherry

Answer 16

@ganeshie8 @zepdrix @Luigi0210 @nincompoop

Answer 17

@paki how so?

Answer 18

@sweetburger plz help

Answer 19

imma tag everyone on openstudy
@agreene @Anvher @AkashdeepDeb @sidsiddhartha @shamil98 @RaphaelFilgueiras @morningskye123 @No.name @Cydney_Morgan @zepdrix

Answer 20

lol I got it wrong

Answer 21

oh i sorry :(

Answer 22

@superhelp101 im so confused right now

Answer 23

it's all good @superhelp101 haha

Answer 24

do worry about sorry that i tagged yah, didn't know :(

Answer 25

btw, knowing what
∆H = - <amount>kJ
exothermic
endothermic
all mean would help you get the correct answer in the future.

Answer 26

Why was I tagged lol? I suck in chemistry.

Answer 27

sorry xDDD

Answer 28

Lol it's fine

Answer 29

@agreene well I know - delta h means that it's exothermic, but what else does that mean in the problem?? Does that mean the reactants have higher energy than the products? or vice versa?

Answer 30

it being negative tells you if it's endothermic or exothermic, which also tells you about the enthalpy (which is what the H is)

Answer 31

it releases energy

Answer 32

I think

Answer 33

right, so that would be exothermic
exo- comes from greek to release thermic from greek as well relating to temperature

Answer 34

@agreene so since it's negative, it's exothermic, but which side of the equation has more energy?

Answer 35

Yeah, chemistry does pay off

Answer 36

@morningskye123 your better at chem then me !

Answer 37

@MacAttack123315 did you get it right or wrong?

Answer 38

the \(\Delta\text{H}_o\) is the reaction, so if it's always talking about the energy (enthalpy) to move across the arrow

Answer 39

@morningskye123 wrong haha

Answer 40

What did you pick?

Answer 41

B

Answer 42

@agreene what do you mean?

Answer 43

It was A

Answer 44

I'm kind of sure

Answer 45

one sec, trying to remember enthalpy lol... i havent had a chem class in like 6 years

Answer 46

you're good, you're good :)

Answer 47

no, C my bad because the products a lower

Answer 48

oh its cause of the state change. enthalpy favours gasses (more random association of atomic energy) then liquids then solids, so moving 6 Oxy to solid is the issue.
second section on this link explains it better than I can:
http://chemwiki.ucdavis.edu/Physical_Chemistry/Thermodynamics/State_Functions/Enthalpy

Answer 49

if delta h has a negative sign, then that means that the reaction is exothermic and heat is released

Answer 50

Ughh... not being rude or anything but do I get a metal for participating? lol

Answer 51

So I would say C. as well

Answer 52

@morningskye123 I'll give you one ;)

Answer 53

okay ty so much!! I can retake it so i'll get it this time

Answer 54

and @morningskye123 I tried to give you one, but it's not working