Answer:
Acetylene: -1,256 kJ/mol
Ethanol: -1,277 kJ/mol
The combustion of 0.25 mol of an unknown organic compound results in the release of 320 kJ of energy. Which of the compounds in the table could be the unknown compound?- Answer: Ethanol
To answer this problem, we write first the stoichiometric equation. Thus we have,
Cu2S + O2 => 2Cu + SO2
Next, we check if the equation is balanced or not.
(left) (right)
2 Cu = 2 Cu
1 S = 1 S
2 O = 2 O
So the stoichiometric equation is balanced, let's proceed in solving the theoretical yield of Cu given 5 g of Cu2S.
First, we solve for Cu2S in moles,
5 g Cu2S x <u>1 mol Cu2S </u> = 0.0314 mol Cu2S
159.16 g Cu2s
Secondly, convert moles of Cu2S to moles Cu. Note for every mole of Cu2S we get 2 moles of Cu. Thus,
0.0314 mo Cu2S x <u> 2 mol Cu </u> = 0.0628 mole Cu<u>
</u> 1 mol Cu2S
Lastly, we convert mole Cu to g Cu via multiplying by Cu's MW.
0.0628 mole Cu x <u>63.546 g Cu </u> = 3.99 g Cu or 4 g Cu<u>
</u> 1 mole Cu
<em>ANSWER: 4 g Cu</em>
B. Magnesium. Periodic tables can help!
:)
I can be used for thyroid cancer or in nuclear
Answer:
Crust (the surface)
Upper Mantle (dense magma)
Lower Mantle (less dense magma)
Outer Core (pure liquid material)
Inner Core (dense material)
Hope that helps