Answer: 530 hours
Explanation:
The reduction of Nickel ions to nickel is shown as:
of electricity deposits 1 mole of Nickel
1 mole of Nickel weighs = 58.7 g
Given quantity = 18.0 kg = 18000 g (1kg=1000g)
58.7 g of Nickel is deposited by 193000 C of electricity
18000 g of Nickel is deposited by =
of electricity
where Q= quantity of electricity in coloumbs = 59182282.8C
I = current in amperes = 31.0 A
t= time in seconds = ?

(1h=3600 sec)

Thus 530 hours are required to plate 18.0 kg of nickel onto the cathode if the current passed through the cell is held constant at 31.0 A
The Kelvin temperature of a substance is directly equal to the avg kinetic energy of particles of a substance. Hope that is what your looking for
Answer:
102g of crystals
Explanation:
When the Cr(NO₃)₃⋅9H₂O is dissolved in water at 15°C, the maximum mass that water will dissolve in the equilibrium is 208 g per 100g of water. When you heat the water, this mass will increases.
In this problem, at 35°C the water dissolves 310g in 100g of water, as in the equilibrium at 15°C the maximum mass is 208g, the mass of crystals that will form is:
310g - 208g = <em>102g of crystals</em>
<em>-Crystals are the Cr(NO₃)₃⋅9H₂O that is not dissolved-.</em>
I hope it helps!
Answer: The final pressure is 34.48kPa
Initial Pressure P1 = 55.16kPa
Initial Volume V1 = 0.500L
Final Pressure P2 = ?
Final Volume V2 = 0.800L
Boyle's law P1V1 = P2 V2
P2 = P1V1/V2
P2 = 55.16*0.5/0.8
P2 = 34.48kPa