Pick the balanced equation for each of the following changes. Make sure \"heat\"
ID: 994191 • Letter: P
Question
Pick the balanced equation for each of the following changes. Make sure "heat" is in appropriate place (if at all). The combustion of 1 mol of liquid ethanol (C_2H_5OH) C_2H_6O(l) + 3O_2(g) rightarrow 2CO_2(g) + 3H2O(g) + heat C_2H_6O(l) + 3O_2(g) + heat rightarrow 2CO_2(g) + 3H_2O(g) C_2H_6O(l) + 3O_2(g) rightarrow 2CO_2(g) + 3H_2O(g) C_2H_6O(l) + 3O_2(g) rightarrow 2CO_2(l) + 3H_2O(g) + heat The formation of 2 mol of nitrogen dioxide from its elements (heat is absorbed) N_2(g) + 2O_2(g) rightarrow 2NO_2(g) + heat N_2(g) + 2O_2(g) + heat rightarrow 2NO_2(l) N_2(g) + 2O_2(g) + heat rightarrow 2NO_2(g) N_2(g) + 2O_2(g) rightarrow 2NO_2(l) + heatExplanation / Answer
1) Combustion of 1 mole of ethanol: Combustion is the net exothermic reaction i.e. heat is evolved out.
Balanced chemical equation:
C2H5OH (l) + 3O2(g) ------------> 2CO2 (g) + 3H2O (g) + Heat. …………..(option-A)
In combustion reaction, large amount of heat is released. The products are in gaseous phase.
=========================
2) Formation of 2 moles of NO2 (g) from its elements N2 (g) and O2 (g) [Heat absorbed]:
Balanced chemical equation:
N2 (g) + 2O2 (g) + heat --------------> 2NO2 (g) ………………(Option-C)
Gaseous states are standard elemental states for N2, O2, NO2 hence all appear in gaseous state.
====================XXXXXXXXXXXXXXXXXXXX=======================