Can someone please answer and explain these chemistry problems for me. 1. How ma
ID: 512223 • Letter: C
Question
Can someone please answer and explain these chemistry problems for me.
1. How many grams of calcium may be formed by the passage of 3.23 amps for 3.02 hours through an electrolytic cell that contains a molten calcium salt. Correct Answer: 7.30
2. How many grams of radium may be formed by the passage of 2.63 amps for 2.31 hours through an electrolytic cell that contains a molten radium salt. Correct Answer: 25.61
3. How long (in hours) must a current of 9.29 amps be passed to produce 57.1 g of lead metal from a solution of aqueous lead(IV)nitrate? Correct Answer: 3.18
Cr(s) and Cu2+(aq) to give Cu(s) and Cr3+(aq)
Use the reduction potentials for Cr3+(aq) is -0.74 V and for Cu2+(aq) is +0.340 V.
2. How many grams of radium may be formed by the passage of 2.63 amps for 2.31 hours through an electrolytic cell that contains a molten radium salt. Correct Answer: 25.61
3. How long (in hours) must a current of 9.29 amps be passed to produce 57.1 g of lead metal from a solution of aqueous lead(IV)nitrate? Correct Answer: 3.18
4. What is the value of Go in kJ at 25 oC for the reaction between the pair: Correct Answer: -620Cr(s) and Cu2+(aq) to give Cu(s) and Cr3+(aq)
Use the reduction potentials for Cr3+(aq) is -0.74 V and for Cu2+(aq) is +0.340 V.
Explanation / Answer
1)
i = 3.23 A
t = 3.02 hours = 3.02 x 60 x 60 = 10872 sec
F = faraday = 96485 C
E = equivalence weight = 40 / 2 = 20
from faraday law :
W = E x i x t / F ----------------- > formula
W = 20 x 3.23 x 10872 / 96485
W = 7.30 g
mass of calcium deposited = 7.30 g