#GetReal -depaima × Hollywood T akes a Knee × ,11 ACCEPTABLE FORMS OF × schedule
ID: 556960 • Letter: #
Question
#GetReal -depaima × Hollywood T akes a Knee × ,11 ACCEPTABLE FORMS OF × schedule C | ezto.mheducation.com/hm.tpx value: 5.88 points Ch. Ex. 102 -Hess's Law: Nitrogen Oxides 1 out of 3 attempts Enter your answer in the provided box The chemistry of nitrogen oxides is very versatile. Given the following reactions and their standard enthalpy changes, (1) NO(g ) + NO2(g ) N203(g ) (2) NOg ) +NO2(g) +02(g) N2O5(g) (3) 2N02(g) N3O4(g) (4) 2N0g ) + O2(g ) 2NO2(g ) (5) N205(s ) N205(g ) AHrn =-39.8 kJ MInn_-112.5 kJ AH -114.2 kJ AI subl -54.1 kJ Calculate the heat of reaction for N203(g) + N2Os(s) 2N-04(g) kJ References eBook & Resources Multipart Answer Chapter 6 Thermochemistry Energy Flow and Chemical Change Gas Laws Post Lab.pdf Gaslaws AY2017-18pdiExplanation / Answer
We must apply Hess law so:
N2O3 is reuqired on the left side
from the list, only N2O3 is found in rxn 1
invert rxn1
N2O3(g) = NO(g) + NO2(g) H= 39.8
now, we need N2O4 so, from RXN 3, multiply by 2 and add
4NO2(g) = 2N2O4(g) H = -57.2*2 = -114.4
add both
4NO2(g) + N2O3(g) = NO(g) + NO2(g) +2N2O4(g) H= 39.8-114.4 = -74.6
3NO2(g) + N2O3(g) = NO(g) + 2N2O4(g) H= -74.6
now... add N2O5(s) via addition of rxn 5
N2O5(s) + 3NO2(g) + N2O3(g) = NO(g) + 2N2O4(g) + N2O5(g) H= -74.6 +54.1 = -20.5
now... get rid of N2O5(g) by:
additino of RXN2, inverted
N2O5(g) = NO(g) + NO2(g) + O2(g) H = 112.5
add to
N2O5(s) + 3NO2(g) + N2O3(g) = NO(g) + 2N2O4(g) + N2O5(g) H= -74.6 +54.1 = -20.5
N2O5(g) + N2O5(s) + 3NO2(g) + N2O3(g) = NO(g) + 2N2O4(g) + N2O5(g) + NO(g) + NO2(g) + O2(g) H= -20.5+112.5 = 92
simplify
N2O5(s) + 2NO2(g) + N2O3(g) = 2NO(g) + 2N2O4(g) + O2(g) H= 92
now, get rid of NO2(g) via:
add RXN4
2NO(g) + O2(g) = 2NO2(g) H = -114.2
N2O5(s) + 2NO2(g) + N2O3(g) = 2NO(g) + 2N2O4(g) + O2(g) H= 92
add
2NO(g) + O2(g) + N2O5(s) + 2NO2(g) + N2O3(g) = 2NO(g) + 2N2O4(g) + O2(g) + 2NO2(g) H= 92 -114.2
simplify
N2O3(g) + N2O5(s)= 2N2O4(g) ) H= 92 -114.2 = -22.2 kJ
HRxn = -22.2 kJ
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.