Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 (Page 3 of 14) in pdf

Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 Page 3

9) A s ystem u ndergoes a p rocess c onsisting o f t he f ollowing t wo s teps:

Step 1 : T he s ystem a bsorbs 7 3 J o f h eat w hile 3 5 J o f w ork i s d one o n i t.

Step 2 : T he s ystem a bsorbs 3 5 J o f h eat w hile p erforming 7 2 J o f w ork.

C alculate t he c hange i n i nternal e nergy f or t he o verall p rocess ( in J ).

71J

10) T he v olume o f a n i deal g as i s d ecreased f rom 5 .0 L t o 5 .0 m L a t c onstant p ressure o f 2 .0 a tm.

C alculate t he w ork a ssociated w ith t his p rocess ( in J ). W ATCH Y OUR U NITS!!!

1008.99 J

11) T he r eaction o f n itrogen w ith h ydrogen t o m ake a mmonia i s

( g) + 3 H

( g) 2 HN

( g)

ΔH = -‐‑ 9 2.2 k J

What i s t he v alue o f Δ E ( in k J) i f t he r eaction i s c arried o ut a t a c onstant p ressure o f 4 0.0 a tm a nd t he

volume c hange i s -‐‑ 1 .12L? W ATCH Y OUR U NITS!!!

-‐‑ 8 7.6752 k J

12) A s trip o f m agnesium o f m ass 1 5 g i s d ropped i nto a b eaker o f d ilute h ydrochloric a cid. W hat w ork i s

done o n t he s urrounding a tmosphere ( 1.00 a tm p ressure, 2 5°C) b y t he s ubsequent r eaction?

-‐‑ 1 525 J

13) C alculate t he w ork d one ( in j oules) b y a c hemical r eaction i f t he v olume i ncreases f rom 3 .2 L t o 3 .4 L

against a c onstant e xternal p ressure o f 3 .6 a tm. W hat i s t he s ign o f t he e nergy c hange?

-‐‑ 7 2.72 J

14) W hen s olutions c ontaining s ilver i ons a nd c hloride i ons a re m ixed, s ilver c hloride p recipitates:

(aq) + C l

(aq) → A gCl(s) ∆ H = – 65.5 k J

–

a) Calculate ∆ H f or t he f ormation o f 2 .00 m ol o f A gCl.

-‐‑ 1 31 k J

b) Calculate ∆ H f or t he f ormation o f 2 .50 g o f A gCl

-‐‑ 1 .14 k J

15) Y ou a re g iven ∆ H f or a p rocess t hat o ccurs a t c onstant p ressure. W hat a dditional i nformation i s

needed t o d etermine ∆ E f or t he p rocess?

Change i n v olume

Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 Page 3