The solubity of copper 11 sulphate at 85°C is 60g in 100g of water and at 15°C is 18.8g in 100g of water. If 120g of solution saturated at 85°C we're cooled to 15°C,what mass of copper 11 sulphate crystals would be deposited?
From the given information, we can see that the solubility of copper II sulphate decreases as temperature decreases. This means that as the saturated solution cools down, more copper II sulphate will come out of solution and form crystals.
To calculate the mass of copper II sulphate crystals that would be deposited when the solution is cooled, we first need to calculate how much copper II sulphate is actually dissolved in the solution when it is at 85°C. We can do this by using the following equation:
mass of copper II sulphate = (solubility at 85°C / 100) x mass of solution
mass of copper II sulphate = (60 / 100) x 120 = 72 g
So, when the solution is at 85°C, there are 72 g of copper II sulphate dissolved in it. When the solution is cooled to 15°C, some of this copper II sulphate will come out of solution and form crystals.
To calculate the mass of copper II sulphate that will be deposited, we need to know how much of the dissolved copper II sulphate will remain in solution at 15°C. We can do this by using the solubility at 15°C:
solubility at 15°C = 18.8 g / 100 g of water
So, at 15°C, the solution can only hold 18.8 g of copper II sulphate in 100 g of water. All of the excess dissolved copper II sulphate will come out of solution and form crystals.
To calculate the mass of copper II sulphate crystals that will be deposited, we need to subtract the amount of dissolved copper II sulphate at 15°C from the amount that was dissolved at 85°C:
mass of copper II sulphate crystals = mass of copper II sulphate at 85°C - mass of copper II sulphate at 15°C
mass of copper II sulphate crystals = 72 - (18.8 / 100) x 120 = 52.64 g
Therefore, 52.64 g of copper II sulphate crystals would be deposited when 120 g of solution saturated at 85°C is cooled to 15°C.
To determine the mass of copper (II) sulfate crystals that would be deposited, we need to find the difference between the amount dissolved at 85°C and 15°C.
1. Calculate the total amount of copper (II) sulfate dissolved at 85°C:
Mass of copper (II) sulfate at 85°C = 60g/100g of water * 120g of solution
= 72g
2. Calculate the total amount of copper (I) sulfate dissolved at 15°C:
Mass of copper (II) sulfate at 15°C = 18.8g/100g of water * 120g of solution
= 22.56g
3. Find the difference between the two amounts:
Difference = 72g - 22.56g
= 49.44g
Therefore, 49.44g of copper (II) sulfate crystals would be deposited when the solution is cooled from 85°C to 15°C.