Chemistry

Answers to Chapter 13 Study Questions

1. ; T1 = 22 + 273 = 295 K; P2 = 1.07 atm; T2 = ?

2. a) STP: PT = 1 atm; T = 273 K; ; nT = 0.039 + 0.010 + 0.001 = 0.050 moles

; (1.00 atm) = 0.20 atm

 

b) V = ?; STP: T = 273 K, PT = 1 atm; nT = 0.050 mol; PV = nRT

= 1.1 L

 

3. a) PT = PH2 + PH2O; Find PH2O in Table at 19C, PH2O = 16 mmHg

PH2 = PT - PH2O = 756 - 16 = 740. mmHg

b) = 0.974 atm

 

4. V1 = 600. cm3; T1 = 25C = 298 K; P1 = 750. mmHg

V2 = 480. cm3; T2 = 41C = 314 K; P2 = ?

 

5. = 0.178 g/L

 

6. a) 2 C4H10(g) + 13 O2(g) 10 H2O(l) + 8 CO2(g)

b) = 3.2 L O2

c) = 17.9 L CO2

d) = 7.5 x 1023 molecules

 

7. nAr = 0.25 mol; nHe = 0.75 mol; nT = nAr + nHe = 0.25 + 0.75 = 1.00 mol

; = 0.80 atm

 

= 3.93 g/L

 

9. methane = CH4. To find grams, use PV = nRT to calculate n. molar mass (CH4) = 16.0 g/mol

n = ?; V = 28.0 L; T = 68 + 273 = 341 K; P = 2.00 atm.

= 32.0 g

 

10. Find molar volume at 710 mmHg and 36C and then use conversion factors:

T = 36 + 273 = 309 K; = 0.934 atm

= 3.71 L O2

 

11. molar mass = ; so use PV = nRT to calculate n; T = 29 + 273 = 302 K; P = 1 atm

= 28.0 g/mole

 

12. = 0.341 mol CO2; = 0.750 mole CH4;

At constant T and P, = 15.7 L