(A)
An aqueous solution of NH4Cl has a molal concentration of 1.193 mol·kg^-1. Its density is 1.0170 g·mL^-1.

1) Calculate the molar concentration of NH4Cl.

----- mol/L

2)Calculate the mass percent of NH4Cl in the solution.

-----%

3)What is the mole fraction of NH4Cl in the solution?

-----

(B)
What mass (g) of AlCl3 would have to be dissolved in 150 mL of water to give a solution that has a vapour pressure of 4.63·10^3 Pa at 35°C? Assume complete dissociation of the solute and ideal solution behavior. At 35°C, the vapour pressure of pure water is 5.63·10^3 Pa.

-----

(C)
What is the approximate osmotic pressure of a 0.1192 mol·kg^-1 solution of LiCl at 10 °C? The freezing point of this solution is -0.415 °C. Express your answer in Pa.
-----

(D)
The vapour pressure of a mixture of 150 g of acetone and 41.6 g of an unknown compound is 0.866·10^4 Pa at 20 °C. The vapour pressure of pure acetone at 20 °C is 0.737·10^4 Pa, while that of the pure unknown is 1.40·10^4 Pa. What is the approximate molar mass of the unknown?

-----g·mol^-1

2.

3. See what you can do, post it, and then someone can help you from there.

4. what?
help pls

5. mohab, in order for us to help you, we have to see that you've done some work first. It's not our job to remove thought from the equation that is your homework, so once you've posted the thoughts that you've had on this, we may be able to help you, but you first have to show that you've attempted the problem. Sorry, no free answers

6. I understand that, and i apreciate ur reply..
i passed chemistry 1 with my course work and some pushes from the book..
i dont know how i am going to pass chemistry 2.. because i really suck at chemistry.. this assignment has 10% for me, and i dont really know where to get help ..

but i tried solving many times, even had a few friends over to help me but we couldnt figure it out ..

i understand the laws for molar fraction and mass percent ..etc like the equations..
i tried over and over but everytime i tried i would get a different answers, and all the 10^3 or -1 or 6 or w.e just scares me more

7. a1) if you know the density, can you tell me how many kg in a liter? Once you find , if you know how many , can you find the ?

8. Originally Posted by Arcane_Mathematician
a1) if you know the density, can you tell me how many kg in a liter? Once you find , if you know how many , can you find the ?
am really sorry. i didnt understand a word, that was like another language to me..

9. Are you a high school student or are you in a college course? If you don't understand units, I'm not really sure how to simplify things further for you to understand.

10. college course

11. my advice is to drop chem 2 and take an intro physics class, so you can learn how to apply units.

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