Could someone let me know if I answered these questions?
1. How do you classify the liquid pair mineral oil -- H2O, miscible or immiscible? I believe the answer is immiscible because oil and water do not mix.
2. what would be the Molarity of a solution containing 0.5 mole of KBr in 500ML (0.5L) I think the answer is
0.5 mole of KBr/500mL = 0.001M
3. A student made a solution of 10g KCl and 90 g of water, what % solution did he make? I think the answer is 10g of KCL/90g H2O(100) = 11.11% solution.
If I answered these questions incorrectly, I would appreciate it if someone could tell me what I did wrong and tell me how to fix it. Thanking you in advance
1 is ok. 2 and 3 are not.
2. M = mols/L not mols/mL.
M = 0.5mol/0.5L = 1 M
3. % w/w = (mass solute/100 g solution)*100.
Should be [10 g KCl/(90+10)]*100 = [10g KCl/100 g solution]*100 = 10%
1. Your answer is correct. Mineral oil (oil) and water are immiscible, meaning they do not mix together.
2. To determine the molarity of a solution, you need to know the moles of solute and the volume of the solution in liters. In this case, you have 0.5 moles of KBr and a solution volume of 0.5 liters. So the correct calculation would be:
Molarity = Moles of solute / Volume of solution in liters
Molarity = 0.5 mol / 0.5 L = 1 M
So the correct answer is 1 M, not 0.001 M. You made a mistake in converting the volume from milliliters to liters. Remember, there are 1000 milliliters in a liter, so divide the given volume of 500 mL by 1000 to get 0.5 L.
3. To calculate the percent solution, you need to divide the mass of the solute by the total mass of the solution and multiply by 100. In this case, you have 10 g of KCl and 90 g of water, so the calculation would be:
Percent solution = (Mass of solute / Total mass of solution) * 100
Percent solution = (10 g / (10 g + 90 g)) * 100
Percent solution = (10 g / 100 g) * 100
Percent solution = 10%
So the correct answer is 10%, not 11.11%. You made a mistake in the calculation. The total mass of the solution should have been 100 g (10 g KCl + 90 g H2O).
You were close in your answers, but made a couple of mistakes in the calculations. Make sure to double-check your conversions and calculations, and you'll be able to find the correct answers.