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Physical Chemistry

H2O yield in mL from Na2CO3 + 2HCl

I have worked this problem many different ways and cannot seem to set it up correctly. Na2CO3 + 2HCl => 2NaCl + CO2 + H2O I have 36.53g of sodium carbonate reacting with 32.94g of hydrchloric acid. I am trying to find how many mL of water are produced from this reaction.

Electrochemistry and concentration

1. a) A copper refining cell is operating with an electrolyte which contains 0.05 m Sn2+. At what concentration of Cu2+ will the tin start to plate out in preference to the copper? The cell temperature is 40°C. b) A polarization potential arises from a concentration difference between ions in the neighborhood of the el

Gas density calculations

A gas was found to have a densitiy of .08747 mg/ml at 17.0 degree C and a pressure of 76o torr. What is its molecular mass? What type of gas most likely is this?

Lasers and gas mixtures

A certain laser uses a gas mixture made up of 9.00 g HCL, 2.00 g H2, and 165.0 g Ne. What pressure is exerted by the mixture in a 75.0 L tank at 22 degree C? Which gas has the smallest partial pressure?

A 100 ml sample of .10 molar NAOH solution was added

A 100 ml sample of .10 molar NAOH solution was added to 100 ml of .10 molar H3C6H5O7. After equilibrium was established, which of the ions listed below was present in the greatest concentration? A) H2C6H5O7^- B) HC6H5O7^2- C) C6H5O7^3- D) OH E) H^+ Please provide thorough explanation for this question.

Relationship between Refractive index and Mole Fraction

How can you use refractive indices to calculate weight % composition of a distillate and its residue? How can you convert the weight % composition to mole fractions? Could you please show me how they relate in mathematical form?

Rates and electrochemistry

1. Step 1: Cl2 ------ 2Cl (fast) Step 2: CHCl3 + Cl -------- CCl3 + HCl (slow) Step 3: CCl3 + Cl ------------CCl4 (fast) Identify the rate determining step, reaction intermediates and the experimental rate law (intermediates can not be in the rate law) 2. For the half-reaction XeF2(aq) +

Rates and electrochemistry

The numerical value of the rate constant for the gaseous reaction 2N2O5------- 4NO2+ O2 was found to be 5.8*10-4. The initial concetration of N205 was 1.00mol/L. Assuming all measurements are recorded in seconds, determine the tim required for the reation to be 60% complete if the reaction is second order

Thermodynamics Initial and Final Volumes

1. 5.30 moles of gas, initially at 25 degrees celcius and 5.00 atm pressure, was allowed to expand adiabatically( with no heat exchange between systen and surroundings) against a constant external pressure of 1.50 atm until the initial volume had trebled. The heat capacity of the gas was known to be 37.1 J/ degree celuius mol

Change of Internal Energy, Entropy, Volume with Temperature

The two figures show Cp VS T for various transitions. I need to know what the graph would look like for: 1. u (internal energy) vs T 2. S (Entropy) vs T 3. and V vs T for a first order (discontinuous) transition. Extra Info: FOr the equilibrium phase transitions at constant T and P (temperature and pressure) t

Electrode Chemistry

An ammonium ion selective electrode responds to both NH4+ and H+, but not to NH3. (pKa=9.244 for NH4+) A) What pH conditions must be imposed to ensure the electode properly represents toe activity of NH4+ B) Why is the ionic strength an important factor when using this or any ISE? How can you compensate for this effect?

Study of a first-order reaction`

In the study of a first-order reaction, A--->B, it is found that A/Ao=0.125 after one hour. The system initially consisted of 0.20 mole of a gaseous A at 25 degrees C and 1 atm. Calculate the initial rate of reaction in moles of A reacting per minute.

Steady State Assumption

For the following mechanism: N205------>k1<--------k2 N02 + N03 N0 + N03 ------>k3 2N02 Using the steady-state assumption, find the expression for dPN02/dt Note. The k1 is on top of the right pointing arow and k2 is below the left pointing arrow and the arrows are like they are in equilibriu


How would you prepare a liter of "carbonate buffer" at a pH of 10.10? Ka = 4.2 times ten to the negative 7(carbonic acid) Ka = 4.8 times ten to the negative 11(bicarbonate ion) It says the key to solving the problem is picking the correct Ka value. How do I know which one to work with?

Find Delta Smix, Delta Gmix, Delta Hmix, and Delta Vmix

Find delta Smix, delta Gmix, delta Hmix, and delta Vmix if 125 g of benzene and 25 g of naphthalene are mixed at 60 degrees C. Assume the solution to be ideal. The molecular weights of benzene and naphthalene are 78.12 g/mol and 128.19 g/mol respectively.

AP Chemistry Test Review: Gases

(See attached file for full problem description) --- 31. A sample of H2 gas occupies 615 mL at C and 575 mm Hg. When the gas is cooled, its volume is reduced to 455 mL and its pressure is reduced to 385 mm Hg. What is the new temperature of the gas? 54. Hydrogen can be made in the "water gas reaction." If you

Blending of Wines with Acid

I need some help with this question: Two wines are available for blending: One tank of 1000 L has a Titratable Acidity of 9.0 g/L and another tank containing 2000 L has a Titratable Acidity of 0.6 g/L. How much volume do you need to blend to make the 9.0 g/L Titatrable Acid wine equivalent to 7.2 g/L? What is the final volu

Calculations with Ideal Gas Laws

I need to find a simple way to convert gases expressed as mol % to volume percent. Pressure and temperature are constant. For example, what volume percent would water vapour be if given as 1.52 mol %?

Free Energy Change of a Reaction

Consider the combustion reaction for propane below. CH3CH2CH3(g)+5O2(g)-------->3 C02(g)+4H20(g) a) Determine the delta G standard state at 298 K from the following standard state values at T= 298 S(CH3CH2CH3)=269.9 J/K mol S(C02)= 213.7 J/K mol S(H20)=188.8 J/K mol S(02)=205.1 J/ K mol delta H(CH3CH2CH3)=-103.9 kJ/mol

Relationship of Enthalpy with P and T

Show that the partial of H with respect to P at constant T =0 for an ideal gas. Hint: start with dH=VdP+TdS. Divide by dP and impose constant T. Use a maxwell relation from dG.

Heat Capacity of a Gas

The heat capacity of a gas is given by Cp=a+bT where a and b are constants: a) Determine delta S for heating the gas from T1 to T2 at constant P b) Determine delta G for heating the gas from T1 to T2 at constant P HINT: the integral lnx dx= x ln x-x

Entropy Change Delta for Argon Gas

Find the entropy change delta for argon gas undergoing the following temperature and pressure changes: good Ar(g),P=1 atm, T=300 K------> Ar(g), P=10 atm, T=500K.

Ions being reduced or oxidized

*** Please see file for full description*** 1. Into each of three potatoes insert 1 copper and 1 zinc probe. The probes should be inserted to a medium depth inside the potatoes and should be spaced within about an inch of each other. The probes should NOT touch inside or outside of the potato. IMPORTANT: To illuminate an