# Recent content by TypeFun

1. ### Molarity homework problem

I'm still struggling. I've calculated the grams of Na2S2O3 = 1.58 g, but I'm still confused as to how I get the molarity of S2O3
2. ### Molarity homework problem

It does not give the number of moles per trial. The question written above is all the information given. The total volume is 7.00 mL. Is that how much volume of finished solution would be in each trial?
3. ### Vapor Pressue of the Solution

Homework Statement If you dissolve 9 g of urea (60.06 g/mol) in 10 mL of water, what is the vapor pressure of the solution at 24 C? Assume the density of water is 1.00 g/mL and the vapor pressure of pure water at 24 C is 22.4 mmHg. Homework Equations Henry's Law, maybe? I'm not sure...
4. ### Freezing Point Question

Homework Statement Wine that is 28.4% ethanol by wt is set outside. Will it freeze if the temp drops to -10 C? (assume water is the solvent) Homework Equations \DeltaTfp = kfp*molality of solute The Attempt at a Solution 2.84 g of ethanol/10 g total =.284 mole \DeltaTfp= -10 ?
5. ### Henry's Law

Homework Statement What mass of O2 can dissolve in 1L of water @ 25 C if the partial pressure of O2 is 40 mmHg? Homework Equations Henry's Law: partial pressure = kH*concentration kH of O2 = 769.2 L*atm/mol The Attempt at a Solution 40 mmHg / 769.2 = concentration
6. ### Chemistry Molality and Mole Fraction

Homework Statement A 10% (by wt) solution of KNO3 would have what molality and what mole fraction Homework Equations mole fraction = moles of KNO3/total moles wt % = # g of solute/total g molality = # moles KNO3/kg H2O The Attempt at a Solution 1 g KNO3/10 g total 1 g KNO3/101.1...
7. ### Preparation of a 250 mL .25 molal solution of CaCl2

Homework Statement Describe in detail how you would prepare 250 mL of a .25 molal solution of CaCl2 Homework Equations CaCl2: 110.98 g/mol molality = #moles of solute/kg of solvent
8. ### Molarity homework problem

Can anyone help me out with this? I'm stuck.
9. ### Physics 2 Units

So the correct unit is a Newton?

Yes? No?
11. ### Physics 2 Units

Assuming, I should use the formula given by the teacher. the units are: V/C*m, right?
12. ### Molarity homework problem

Hmm. Well that's really not that helpful to me. Do you have a hint on what I should do? I mean, I wouldn't be asking on this forum if I wasn't in need of help.
13. ### Lab Preparation Using a solid, DI water, a balance, and a flask

Hey thanks. My new number is 12.16 g of K2S2O8. Would that change my answer to: Using the balance, measure out 12.16 g of K2S2O8. Add that to a volumetric flask. Pour DI water into the flask, until 250 mL has been reached. Does that sound correct?
14. ### Physics 2 Units

This was the formula we were given to calculate Lamda: Lambda = 9.99 V / [2*ke*ln(.0860 m / .0055 m)]
15. ### Physics 2 Units

It does. Lambda = 9.99 V / [2*ke*ln(.0860 m / .0055 m)] ke = Coulomb's Constant, C I think that makes its V/C*m