Given that,
Work done by the system = 125 J
Energy released when it cools down = 438 J
To find,
The change in internal energy.
Solution,
As heat is released by the system, Q = -438 J
Work done by the system, W = -125 J
Using the first law of thermodynamics. The change in internal energy is given by :

So, the change in internal energy is 563 J.
Answer:
0,31%
Explanation:
For the reaction:
I₂ + 2 S₂O₃²⁻ → 2 I⁻ + S₄O₆²⁻
0,043 L × 0,117 M of sodium tiosulfate = 5,031x10⁻³ moles of S₂O₃²⁻
5,031x10⁻³ moles of S₂O₃²⁻ ×
= <em>2,5156x10⁻³ moles of I₂</em>
These moles of I₂ were produced from:
ClO⁻⁻ + 2 H⁺ + 2 I⁻ → I₂ + Cl⁻ + H2O
2,5156x10⁻³ moles of I₂ ≡ moles of NaClO
2,5156x10⁻³ moles of NaClO ×
=<em> 0,187 g of NaClO</em>
Thus, percentage composition by mass is:
=<em> 0,31%</em>
I hope it helps!
Question: The question is incomplete. Below is the complete question and the answer;
While ethanol (CH3CH2OH is produced naturally by fermentation, e.g. in beer- and wine-making, industrially it is synthesized by reacting ethylene CH2CH2) with water vapor at elevated temperatures. A chemical engineer studying this reaction fills a 50.0 L tank at 22. °C with 24. mol of ethylene gas and 24. mol of water vapor. He then raises the temperature considerably, and when the mixture has come to equilibrium determines that it contains 15.4 mol of ethylene gas and 15.4 mol of water vapor The engineer then adds another 12. mol of water, and allows the mixture to come to equilibrium again. Calculate the moles of ethanol after equilibrium is reached the second time. Round your answer to 2 significant digits.
Answer:
Number of moles of ethanol = 11 mol
Explanation:
SEE THE ATTACHED FILE FOR THE CALCULATION