General Chemistry Answers

For each reaction below, indicate in which direction the equilibrium shifts when the stated stress is applied to the system. Write R if the reaction shifts to the right, L if the reaction shifts to the left, or NC if there is no change.

A. Reaction: PCl5(g) <==> PCl3(g) + Cl2 + heat

Stress: temperature increase

B. Reaction: CO(g) + Fe3O4(s) <==> CO2(g) + 3FeO(s)

Stress: volume. Increase

C. Reaction: C2H2(g) + H2O(g) <==> CH3CHO(g) + heat

Stress: temperature decrease

D. Reaction: 2NO(g) + H2(g) <==> N20(g) + H2O(g) + heat

Stress: volume decrease

E. Reaction: Heat + H2(g) + l2(g) <==> 2Hl(g)

Stress: temperature decrease

F: H2(g) + Cl2(g) <==> 2HCl(g) + heat

Stress: volume decrease

At 773K, the reaction 2NO(g) + O2(g) ==> 2NO2(g) produces the following concentrations:

[NO] = 3.49x10^-4 M; [O2] = 0.80 M; [NO2] = 0.25 M.

A. What is the equilibrium expression for the reaction? Show your work.

B. What is the equilibrium constant for the reaction? Show your work.

Consider the reaction below at 25° C for which ΔS = 16.1 J/K. Show your work.

CH4 (g) + N2(g) + 163.8 kJ ==> HCN(g) + NH3(g)

At what temperature will this reaction be spontaneous?

For each of the following molecules, write the Lewis structure(s), predict the molecular structure (including bond angles), give expected hybrid orbitals on the central atom, and predict the overall polarity.

a. OF2 b. AsF5 c. IF5

Use the localised electron model to describe the bonding in hydrogen cyanide and phosgene (COCl2)

Titration of 0.2121 g of pure Na2C2O4 (134.00 g/mol) required 43.31 mL

of KMnO4.What is the molar concentration of the KMnO4 solution? The

chemical reaction is

2MnO4 + 5C2O4+ 16H* ->2Mn+ 10CO2+ 8H2O

describe the preparation of 900 ml of 3 M HNO3 from the commercial reagent that is 70.5% HNO3 (w/w) and has a specific gravity of 1.42

Use the localised electron model to describe the bonding in hydrogen cyanide and phosgene( COCL2)

For each of the following molecules, write the Lewis structure(s), predict the molecular structure (including bond angles), give expected hybrid orbitals on the central atom, and predict the overall polarity. a. OF2 b. AsF5 c. IF5

The standard enthalpy of formation, ΔH˚f of liquid ethanol, C2H5OH(l) @ 25C is -277.63 kJ/mol.  Calculate its heat of combustion at constant pressure from the given reaction, C2H5OH(l)+ 3 O2(g) → 2 CO2(g) + 3 H2O(l). ΔH˚f CO2=-393.50 kJ/mol ΔH˚fH2O= -285.84 kJ/mol