Answer: 20 + 1 + 3.8 + 2.4 +27 = 54.2
Explanation: 20 gallons plus 1 gallon plus 3.8 plus 2.4 plus 27 equals to a total number of 54.2 gallons for the propane.
Answer: The value of enthalpy of the given reaction is 44.000 kJ/mol , that is energy is supplied to water to change into water vapors
Explanation:

Enthalpy of formation of water in liquid state,
Enthalpy of formation of water in gaseous state,


The value of enthalpy of the given reaction is 44.000 kJ/mol, that is energy is supplied to water to change into water vapors.
<span>The Persian Wars mark an important turning point not only in Greek history but, indeed, in the course of all European civilization. First and foremost, because of its victory Greece was saved from the threat of external rule and could develop on its own. Handed this independence, the Greeks chose to follow a path which forever changed the course of modern life. Without their success in this conflict, they would, no doubt, never have had the liberty, means or conviction to invent, discover or create all they did: not just history but philosophy, science, drama, art, architecture, indeed most of the cornerstones of modern civilization.
Another consequence of this victory, less immediate but equally important, was that it prevented the Persians from dominating the lands to the west of Greece—as noted above, it's likely the fertile fields of Italy and Sicily, not the rough dust of Greece, were the real target of Xerxes' imperial designs—and there a tiny settlement called Rome had just begun to sprout, at that moment hardly a dot on the map, but it would later develop into a crucial player in the history of the West. Rome won freedom, too, in the Persian Wars, without ever fielding a single fighter. It's impossible to imagine how vastly different our world would be if Persia had conquered or exterminated the Romans before they'd ever had a chance to grow.
Thus, the Greeks laid the groundwork for later Western culture, and Herodotus the foundation for understanding it. If so many of his facts look suspect or even prove incorrect, if he sometimes seems to set speculation and scandal over sober criticism and science, before condemning him we should recall that he founded this entire enterprise called history, a discipline which still bears the name he gave it. His critics should also bear in mind it's only because Herodotus set us on this path that we can even scorn his methods in the first place. To this most uncommon "common man," we owe an enormous collective debt.</span>
a. volume of NO : 41.785 L
b. mass of H2O : 18 g
c. volume of O2 : 9.52 L
<h3>Further explanation</h3>
Given
Reaction
4 NH₃ (g) + 5 O2 (g) → 4 NO (g) + 6 H2O (l)
Required
a. volume of NO
b. mass of H2O
c. volume of O2
Solution
Assume reactants at STP(0 C, 1 atm)
Products at 1000 C (1273 K)and 1 atm
a. mol ratio NO : O2 from equation : 4 : 5, so mo NO :

volume NO at 1273 K and 1 atm

b. 15 L NH3 at STP ( 1mol = 22.4 L)

mol ratio NH3 : H2O from equation : 4 : 6, so mol H2O :

mass H2O(MW = 18 g/mol) :

c. mol NO at 1273 K and 1 atm :

mol ratio of NO : O2 = 4 : 5, so mol O2 :

Volume O2 at STP :
