The heat required to completely melt the given substance, platinum, we just have to convert first the given mass in mole and multiply the answer to its molar heat of fusion..
Hf = mass x (1/molar mass) x molar heat of fusion
Hf = (85.5 g) x (1 mole/195.08 g) x 4.70 kcal/mol
Hf = 2.06 kcal
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>
Answer:
By giving electricity to copper compound solution.
Explanation:
Electrolysis is one of the major way of refined copper. The copper containing solution has two electrodes.i) positive electrodes called anode. ii) negative electrodes called cathode. When electricity is pass into the copper containing solution electrolysis process is starts and impure copper is formed in anode and pure copper is formed in cathode.
So, We can get pure copper in cathode through electrolysis.
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Answer:
Hydration
Explanation:
In water, ions are surrounded by a sphere of water molecules called a hydration shell. The process of forming this shell is called hydration.
