Methane is the compound CH4, and burning it uses the reaction:
CH4 + O2 -> CO2 + H2O, which is rather exothermic. To find the heat released by burning a certain amount of the substance, you should look at the bond enthalpy of each compound, and then compare the values before and after the reaction. In methane, there are 4 C-H bonds, which have bond energy of 416 kj/mol, resulting in a total bond energy of 1664 kj/mol. O2 is 494 kj/mol. Therefore we have a total of 2080 kj/mol on the left side. On the right side we have CO2, which has 2 C=O bonds, each at 799 kj/mol each, resulting in 1598 kj/mol, and H2O has 2 O-H bonds, at 459kj/mol each, resulting in a total of 2516 kj/mol on the right hand side. Now, this may be confusing because the left hand side seems to have less heat than the right, but you just need to remember: making minus breaking, which results in a total change of 436kj/mol heat evolved.
Now it is a simple matter of find the mols of CH4 reacted, using n=m/mr.
n = 9.5/16.042 = 0.592195 mol
Therefore, if we reacted 0.592195 mol, and we produced 436 kj for one mol, the total amount of energy evolved was 436*<span>0.592195 kj, or 258.197 kj.</span>
Almost always oxidation,
the speed of the reaction is the big difference between fire and explosions
<span>(and slower yet - the "respiration" reactions that keep you alive).</span>
Answer:
<em>D</em><em>.</em><em>They have properties similar to those of their component elements.</em><em> </em>
Explanation:
When elements are joined, the atoms lose their individual properties and have different properties from the elements they are made of .
Answer:
The answer to your question is 1.51 moles of PBr₃
Explanation:
Data
moles of Br = 2.27
moles of PBr₃ = x
Balanced chemical reaction
2P + 3Br₂ ⇒ 2PBr₃
Reactant Element Products
2 P 2
6 Br 6
-Use proportions to find the answer
3 moles of Br₂ ------------------ 2 moles of PBr₃
2.27 moles of Br₂ ------------------ x
x = (2.27 x 2) / 3
x = 4.54 / 3
x = 1.51 moles
