Please help me with this question using a clear explanation step by step. Thanks

Question

Please help me with this question using a clear explanation step by step. Thanks

The study and understanding of thermodynamics is essential to the future of energy use. One example of this connection is in the field of solar energy, where energy is harvested from sunlight. Solar energy is in fact the largest carbon-free option for renewable energy sources, however the efficiency of harvesting the energy must be improved. A photovoltaic cell is a technology that turns sunlight into electricity by employing certain combinations of conductive materials. Many different technologies have been used in these cells. One example is a thermal system where the photovoltaic cell creates a of heat, which can be transferred to domestic hot water heaters. Ionic hydrates can be used in these cells such as sodium sulfate decahydrate. When the hydrate is warmed by sunlight over 32 degree F, the ionic compound dissolves into the water which is an endothermic process. Na_2SO_4(aq) + 10 H_2O(l) rightarrow Na_2SO_4 middot 10H_2O(s) Delta H = -354 kJ/mol Then, at night, when the water cools back below a freezing temperature, the hydrate recrystallizes, which is an endothermic process. This releases heat energy that can be used for heating water in the home. Question To make use of an ionic hydrate for storing solar energy, you place 500.0 kg of sodium sulfate decahydrate on your house roof. Assuming complete reaction and 100% efficiency of heat transfer, how much heat (in kJ) is released into your house at night?

Explanation / Answer

In above reaction 1 mole ammonium sulphate produces 354 kj energy.

So we have to convert 500 kg to moles.

Lets first add mol wt

132.14 + 10(18) = 312.14

we have 500 kg means 500*1000 = 500000 gm of amm. sulphate.

now mole of amm sulphate decahydrate = wt in gram/ mol wt

500000/312.14=1601.84 moles

Now 1 mole produces 354 kj of energy

so 1601.84 moles will produce (1601.84*354)= 5,67,051.36 kj of energy.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.