Answer:
D) 8.40 L H₂O(g).
Explanation:
- The balanced equation for the mentioned reaction is:
<em>2N₂H₄(l) + O₂(g) → N₂(g) + 2H₂O(g),
</em>
It is clear that 2.0 moles of N₂H₄ react with 1.0 mole of O₂ to produce 2.0 moles of N₂ and 2.0 moles of H₂O.
- At STP, 4.20L of O₂ reacts with N₂H₄:
It is known that at STP: every 1.0 mol of any gas occupies 22.4 L.
<u>using cross multiplication:
</u>
1.0 mol of O₂ represents → 22.4 L.
??? mol of O₂ represents → 4.2 L.
∴ 4.2 L of O₂ represents = (1.0 mol)(4.2 L)/(22.4 L) = 0.1875 mol.
- To find the no. of moles of H₂O produced:
Using cross multiplication:
1.0 mol of O₂ produce → 2.0 mol of H₂O, from stichiometry.
0.1875 mol of O₂ produce → ??? mol of H₂O.
∴ The no. of moles of H₂O = (2.0 mol)(0.1875 mol)/(1.0 mol) = 3.75 mol.
- Again, using cross multiplication:
1.0 mol of H₂O represents → 22.4 L, at STP.
3.75 mol of H₂O represents → ??? L.
<em>∴ The no. of liters of water vapor will be produced </em>= (3.75 mol)(22.4 L)/(1.0 mol) = <em>8.4 L.</em>
<em></em>
<em>So, the right choice is: D) 8.40 L H₂O(g).</em>
<em></em>
Answer:
if a 40.0-gram sample of the gas occupies 11.2 liters of space at STP? A balloon is filled with 5 moles of helium gas.
Explanation:
<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>
Answer:
n = 0.573mol
Explanation:
PV = nRT => n = PV/RT
P = 1.5atm
V = 8.56L
R = 0.08206Latm/molK
T = 0°C = 273K
n = (1.5atm)(8.56L)/(0.08206Latm/molK)(273K) = 0.573mol
Explanation:
The balanced equation for the reaction is given as;
2CH3CHO + O2 → 2CH3COOH
If 20.0 g CH3CHO and 10.0 g O2 were put into a reaction vessel, (a)
how many grams of acetic acid will be produced?
First thing's first, we have to find he limiting reactant. This is done by comparing the number of moles of the reactants.
From the equation of the reaction;
2 mol of CH3CHO reacts with 1 mol of O2
From the masses given;
Number of moles = Mass / Molar mass
CH3CHO;
Number of moles = 20 / 44.0526 = 0.454 mol
O2;
Number of moles = 10 / 32 = 0.3125 mol
The limiting reactant is CH3CHO because O2 would be in excess.
Back to the question;
2 mol of CH3CHO produces 2 mol of CH3COOH
0.454 mol would produce x
Solving for x;
x = 0.454 * 2 / 2 = 0.454 mol
Converting to mass;
Mass = number of moles* Molar mass
Mass = 0.454 mol * 60.052 g/mol = 27.26 grams
(b) how many grams of the excess reactant remain after the reaction is
complete
The excess reactant is O2
Number of moles left = Initial Number of moles - Number of moles that reacted
Number of moles left = 0.3125 mol - (0.454 mol / 2)
Number of moles left = 0.0855 mol
Converting to mass;
Mass = 0.0855 mol * 32 g/mol = 2.736 grams
