Ch 11 Problem solving. #31 Step 1: calculate the heat required to evaporate using  H vap 50 g x 2.4 kJ/g = 120kJ convert = 1.2 x10 5 J The solve for.

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Presentation transcript:

Ch 11 Problem solving

#31 Step 1: calculate the heat required to evaporate using  H vap 50 g x 2.4 kJ/g = 120kJ convert = 1.2 x10 5 J The solve for mass using Q = m·C p ·ΔT m = Q/C p ·ΔT 1.2 x10 5 J / (4.18 J/g-K x 13 K) = 2.2x10 3 g H 2 O

#33 1. Q = m·C p of solid ·ΔT 3. Q = m·C p of liquid ·ΔT 2. g  mol then mol x  H fus 4. g  mol then mol x  H vap Step 5 add kJ from # kJ kJ kJ kJ = 105kJ

WDP #48

WDP #44

WDP #46

WDP # 50 part 1

WDP #50 part 2 Your book gives the specific heat of steam as 1.84 J/g-K, while this book gives it as 2.03 J/g-K

WDP #51 With the formula rearranged it would look like: m = Q/C p ·ΔT g H 2 O = 2.26 x 10 3 J 4.18 J/g-K* 15K = 36.0 g H 2 O