# Search results

1. ### 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...
2. ### 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 ?
3. ### 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
4. ### 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...
5. ### 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
6. ### Lab Preparation Using a solid, DI water, a balance, and a flask

Homework Statement Describe how you would prepare exactly 250 mL of .180 M K2S2O8 solution for use. Assume that you have a supply of solid K2S2O8, deionized water, a balance, and a volumetric flask. Also, how many grams of K2S2O8 would you need? Homework Equations The Attempt at a...
7. ### Molarity homework problem

Homework Statement Calculate the initial molarity of S2O32- in each trial given that each trial has 1.00 mL of .010 M Na2S2O3 and a total volume of 7.00 mL. Homework Equations mol = g/(g/mol) M1V1=M2V2 The Attempt at a Solution (1)(.01)=7x .0014=x Homework Statement...
8. ### Physics 2 Units

Homework Statement 1) What are the units for the charge, Q? 2) What are the units for ke*Q? 3) What are the units for - ke*Q / R, R=radius (m) 4) What are the units for 2*ke*\lambda*ln R 5) What are the units for - 2*ke*\lambda 2. The attempt at a solution 1) C, Coulomb's 2) N*m2/C...
9. ### Rate Law+Temperature

Homework Statement Why is it necessary to report the temperature when reporting the rate constant? Homework Equations k*[A]^m*[B]^n The Attempt at a Solution Temperature, like the presence of a catalyst or the concentration of the substance, can have an effect on the reaction rate...
10. ### Electric Fields Lines of a pair of Finite Parallel Plates

Homework Statement Comment on the electric field lines of a pair of finite parallel plates (a) between the plates and (b) near the edges of the plates. Homework Equations The Attempt at a Solution
11. ### Why are electric field lines also referred to as "lines of force"?

Homework Statement Why are electric field lines also referred to as "lines of force"?
12. ### Static Electricity

Homework Statement How would static electricity on your clothes or on your body affect an experiment involving charged objects? Homework Equations Coulomb's Law The Attempt at a Solution The static electricity would attract the objects due to the like charges, assuming the objects...
13. ### Coulomb's Law and Corrected Angle

Homework Statement Corrected Angle, theta, vs Distance, r, demonstrate or relate to Coulomb's Law how? Homework Equations Coulomb's Law The Attempt at a Solution As the distance increases, the force decreases by a factor of 4 because "r" is squared in Coulomb's law. Homework...