Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 (Page 13 of 14) in pdf

Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 Page 13

Calculate t he a mount o f h eat n eeded t o m elt 2 7.0 g o f i ce i f t he h eat o f f usion o f i ce i s 6 .009 k J/mol.

9.003 k J

If 2 7.0 g rams o f i ce a t 0 °C i s a dded t o 1 23 g rams o f w ater a t 1 00°C i n a n i nsulated c ontainer,

calculate t he f inal t emperature. A ssume t hat t he s pecific h eat o f w ater i s 4 .184 J K

-‐‑ 1

67.7˚C

A 5 0 g ram b lock o f a n u nknown m etal a lloy a t 1 00°C i s d ropped i nto a n i nsulated f lask c ontaining

approximately 2 00 g rams o f i ce. I t w as d etermined t hat 1 0.5 g rams o f t he i ce m elted. W hat i s t he

specific h eat c apacity o f t he u nknown a lloy?

0.70 J /g*K

If t he e nthalpy c hange f or t he c ombustion o f p ropane i s – 2220 k J/mole p ropane, w hat q uantity o f

heat i s r eleased w hen 1 k g o f p ropane i s b urned?

(g) + 5 O

(g) → 3 CO

(g) + 4 H

O(l)

ΔH-‐‑ 2 220 k J

-‐‑ 5 0328 k J

Using t he f ollowing t hermochemical d ata, c alculate t he m olar h eat o f c ombustion, Δ H°

o f

combustion

methane, C H

2CH

(g) + 3 O

(g) → 2 CO(g) + 4 H

O(l)

ΔH° = -‐‑ 1 215 k J

2C(s) + O

(g) → 2 CO(g)

ΔH° = -‐‑ 2 21 k J

C(s) + O

(g) → C O

(g)

ΔH° = -‐‑ 3 94 k J

-‐‑ 8 91 k J/mol

Calculate t he s tandard m olar e nthalpy o f f ormation o f m ethane f rom t he d ata g iven i n q uestion 8 ,

your a nswer t o q uestion 8 , a nd t he f ollowing:

( H

O(l)) = -‐‑ 2 86 k J/mol

ΔH°

-‐‑ 7 5 k J/mol

Chapter 5: Thermodynamics Worksheet With Answers - Ap Chemistry 2015-2016 Page 13