Question

Помогите, пожалуйста, с физикой. 8 кл. Происходит электролиз раствора CuSo4. КПД установки - 60%. Какое количество энергии нужно потратить, что бы при напряжении 50 В получить 2 мг меди?

Answer 1

Закон Фарадея:
m=kIt
Масса выделившегося на электроде вещества равна произведению электрохимического эквивалента вещества, силы тока в электролите и времени , в течение которого через электролит проходил ток.
Отсюда следует:
It=m/k
(k меди = 0.33 мг/Кл)
It=6 Кл
КПД можно выразить как отношение энергии, затраченной на электролиз и энергии в целом:
ŋ=Q1/Q
Q=Q1/ŋ
Тепловая энергия, затраченная на электролиз можно найти по формуле:
Q1=UIt
Q=UIt/ŋ
Q=50В*6Кл/0.6=500Дж

Answer 2

Electrolysis of CuSO4 Solution and Efficiency of the Setup

To calculate the amount of energy required to obtain 2 mg of copper through the electrolysis of a CuSO4 solution, we need to consider the efficiency of the setup. The given information states that the efficiency of the electrolysis setup is 60%.

Calculation of Energy Required

The energy required for electrolysis can be calculated using the formula:

Energy = Voltage × Charge

In this case, we are given the voltage (50 V) and the amount of copper to be obtained (2 mg). To calculate the charge, we need to convert the mass of copper to moles and then determine the number of electrons involved in the reaction.

Conversion of Mass to Moles

To convert the mass of copper (2 mg) to moles, we need to know the molar mass of copper. The molar mass of copper (Cu) is approximately 63.55 g/mol.

Moles of Copper = Mass of Copper / Molar Mass of Copper

Converting 2 mg to grams:

Mass of Copper = 2 mg × (1 g / 1000 mg) = 0.002 g

Now, we can calculate the moles of copper:

Moles of Copper = 0.002 g / 63.55 g/mol ≈ 3.15 × 10^-5 mol

Determining the Number of Electrons

In the electrolysis of CuSO4, copper ions (Cu2+) are reduced at the cathode. Each copper ion gains two electrons to form copper metal. Therefore, the number of electrons involved in the reaction is twice the number of moles of copper.

Number of Electrons = 2 × Moles of Copper

Number of Electrons = 2 × 3.15 × 10^-5 mol ≈ 6.30 × 10^-5 mol

Calculation of Charge

The charge can be calculated using Faraday's constant (F), which is approximately 96,485 C/mol The charge is given by:

Charge = Number of Electrons × Faraday's Constant

Charge = 6.30 × 10^-5 mol × 96,485 C/mol ≈ 6.08 C

Calculation of Energy

Now that we have the charge (6.08 C) and the voltage (50 V), we can calculate the energy required using the formula:

Energy = Voltage × Charge

Energy = 50 V × 6.08 C ≈ 304 J

Conclusion

To obtain 2 mg of copper through the electrolysis of a CuSO4 solution at a voltage of 50 V, approximately 304 J of energy needs to be expended. However, it is important to note that the given information states that the efficiency of the setup is 60%. Therefore, the actual energy required would be higher than the calculated value, taking into account the efficiency of the setup.

Please note that the calculations provided are based on the given information and assumptions.