For a given reaction, the heat capacity (CP) of the reactants is 50.0 J/mol K and for the products is 65.0 J/mol K. If the enthalpy of reaction is − 150.0 kJ/mol at 300K, what is the best estimate of ΔrxnH at 320K?

The reaction in the previous question is carried out adiabatically starting at 300 K. What is the final temperature after the reaction goes to completion?

Δ_rxnH₃₀₀ = -150.0 kJ/mol

C_P(reactants) = 50 J/molK

C_P(products) = 65 J/molK

T_f = ? K

What relative masses of dimethyl amine and dimethyl ammonium chloride do you need to prepare a buffer solution of pH = 10.58?

units of answer should be: g of(CH3)2NH per 1g (CH3)2NH2Cl

Calculate the Ka of if 5.0 M HF, 2.7% dissociated:

a) Dissociation equilibria:

b) ICE setup:

c) Amount dissociated:

d) Ka:

12. Calculate the [H+], [OH-] and pH of 0.90 M HC2H3O2; Ka= 1.8 x 10-5.

a) Dissociation equilibria:

b) ICE setup:

c) [H+] and [OH-]:

d) pH:

13. Calculate the [H+], [OH-] pOH and pH 5.0 M NH3; Kb= 1.8 x 10^-5

a) Dissociation equilibria:

b) ICE setup

c) [H+] and [OH-]:

d) pOH and pH

1) The vapor pressure of benzene, C6H6, is 100.0 torr at 26.1 ∘C. Assuming Raoult’s law is obeyed, how many moles of a nonvolatile solute must be added to 100.0 mL of benzene to decrease its vapor pressure by 10.0% at 26.1 ∘C? The density of benzene is 0.8765 g/cm3.

2) Which of the following actions will raise the osmotic pressure of a solution?

What answer should be reported, with the correct number of significant figures, for the following calculation? (249.362 + 41)/63.498 Please explain the significant figures portion.

Given the values of ?H?rxn, ?S?rxn, and Tbelow, determine ?Suniv. Also, predict whether each reaction will be spontaneous or nonspontaneous

A)?H?rxn= 86kJ , ?Srxn= 142J/K , T= 308K

Express your answer using two significant figures.

B)?H?rxn= 86kJ , ?Srxn= 142J/K , T= 762K

Express your answer using one significant figure.

C)?H?rxn= 86kJ , ?Srxn=? 142J/K , T= 308K

Express your answer using one significant figure.

D)?H?rxn=? 86kJ , ?Srxn= 142J/K , T= 404K

Express your answer using one significant figure.

Determine the pH during the titration of 36.0 mL of 0.235 M trimethylamine ((CH₃)₃N, K_b = 6.3×10^-5) by 0.235 M HBr at the following points. (Assume the titration is done at 25 °C.)
Note that state symbols are not shown for species in this problem.

a.) Before the addition of any HBr

b.) After the addition of 15.3 mL of HBr

c.) At the titration midpoint

d.) At the equivalence point

e.) After adding 56.2 mL of HBr

Al(s) + HCl(aq) → AlCl3(aq) + H2(g) 2. According to the equation above, how many grams of aluminum are needed to completely react with 2.19 mol of hydrochloric acid? 3. Sulfur dioxide will react with water to form sulfurous acid SO2(g) + H2O(l) → H2SO3(l) What mass of sulfur dioxide is needed to prepare 27.86 g of H2SO3(l)? 4. The compound P4S3 is used in matches. It reacts with oxygen to produce P4O10 and SO2. The chemical equation is shown below. P4S3(s) + O2(g) → P4O10(s) + SO2(g) What mass of SO2 is produced from the combustion of 0.401 g P4S3? 5. How many moles of Mg3P2(s) can be produced from the reaction of 0.14 mol Mg(s) with 0.020 mol P4(s)? Mg(s) + P4(s) → Mg3P2(s) 6. A 5.95-g sample of AgNO3 is reacted with excess BaCl2 according to the equation AgNO3(aq) + BaCl2(aq) → AgCl(s) + Ba(NO3)2(aq) to give 4.48 g of AgCl. What is the percent yield of AgCl? 7. Sulfur hexafluoride is produced by reacting elemental sulfur with fluorine gas. S8(s) + F2(g) → SF6(g) What is the percent yield if 18.3 g SF6 is isolated from the reaction of 10.0 g S8 and 30.0 g F

how do you determine the number of hydrogen atoms bonded to each carbon in a line-angle formula?

Calculate the millimoles of sodium hypochlorite used in the reaction: 5 mL of a 5.25% solution of Clorox bleach (show detailed calculations). Compare this value with the quantity of diphenylmethanol (millimoles) to be used in the reaction. Would you describe the oxidant as being present in slight excess or large excess?

For H35Cl (ΘV = 4304 K) what is the approximate contribution of vibrational degrees of freedom to the molar constant volume heat capacity at 298 K?

In an adiabatic, constant-volume bomb calorimeter, a combustion of 0.7362g of naphthalene (C10H8) caused the temperature to rise of 5.707 Celcius. The final temperature was 298.000K. The heat capacity of the calorimeter, Ccal was 10290 J/K . (Note: this value of Ccal includes the contribution from water.) The molar enthalpies of formation of CO2(g) and H2O(l) are: -393.522 kJ/mol, -285.830 kJ/mol, respectively Mm(C)= 12.01 g/mol and Mm(H)= 1.001 g/mol.

a.) Calculate deltaUc , deltaUcm , delta Hcm for this combustion reaction.

b.) What are delta Hf and delta Hfm of naphthalene?

A 27 mL solution of .100 M CH3COOH is titrated with a .220 M KOH solution. Calculate the pH after the following additions of the KOH solution:

a) 0 mL

b) 5 mL

what effect would each of the following have on the calculated molar mass of an unknown?

a) The balance was not zeroed before the three weighings of the test tube, sample, water were made. This caused each mass measurement to be 0.102 g greater than it should have been.

b) The thermometer consistently read 0.06 C lower than it should have, over the entire experimental range

c) The masses of the unknown and the solvent (water) were determinded, and the unknown completely dissolved in the water. Just before the jacketed test tube containing the unknown solution was placed in the ice-salt water bath, a small amount of the solution was spilled out of the tube.

d) The unknown contained a smal amount of an insoluble impurity

e) The unknown contained a small amount of a soluble impurity, which had a molar mass lower than that of the pure unknown.

f) A portion of the unknown did not dissolve.