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100

The combination that results in a precipitation forming

a) NaOH(aq) and HCl(aq)

b)NaOH(aq) and FeCl3(aq)

c) NaNO3(aq) and FeCl3(aq)

d) Zn(s) and HCl(aq)


Search "Sigma-Aldrich for Solubility Rules for Ionic Compounds"

What is NaOH(aq) and FeCl3(aq)?

100

What is the molar concentration of a solution made by dissolving 8.56g of sodium acetate in water and diluting to 750.0 mL? The molar mass of NaC2H3O2 is 82.03 g/mol.

0.139 M

100

If a system's internal energy increases by 250kJ after the addition of 375kJ of energy as heat, what was the value of the work in the process?

should it be positive or negative?

-125kJ

100

What is the best Lewis structure of nitrogen monoxide?

  .    ..
: N=O:

100

which set of quantum number is correct and consistent with n=4?

A) l=3 ml=-3 ms=+1/2
B) l=4 ml=+2 ms= -1/2
C) l=2 ml=+3 ms=+1/2
D) l=3 ml=-3 ms=+1

A) l=3 ml=-3 ms=+1/2

200

What are the spectator ion(s) in this reaction?

HC2H3O2(aq) + NaOH(aq) -> NaC2H3O2(aq) + H2O(l)

Na+ Only

200

What is the final concentration when 28.2 mL of an 11.8 M solution is diluted to 100.0 mL?

3.33 M

200

A piece of Iron is heated to 95.0 degrees celsius and then placed in an insulated vessel containing 250g of water at 25.0 degrees celsius. when the system comes to equilibrium the temperature of the system is 35.0 degrees celsius. What is the mass (in g) of the iron? Assume no heat is lost to the surroundings.

Specific Heat: J/g⋅K
Iron                 0.450
Water               4.184

387g

200

The Lewis dot structure of ethanol is given below. Estimate the enthalpy of combustion of ethanol (C2H5OH) using the bond enthalpies in the table.

C2H5OH + 3O2 -> 2CO2 + 3H2O
   
    H H                 Bond Enthalpy: kJ/mol
    |  |  ..                    C-H       413
H-C-C-O-H           C-C       348
    |  |  ..                    C-O       358
   H  H                 C=O      799
                          O-H       463
                          O=O      495

-1255kJ/mol

200

What is the ground state electron configuration of the manganese atom, Mn?

1s22s22p63s23p63d54s2

300

The balanced net ionic equation for the reaction of CuCl2(aq) and H2(g)

What is Cu2+(aq) + H2(g) -> Cu(s) + 2H+(aq)?

300

What is the molar concentration of a solution when 7.00 mL of a 3.25 M aqueous solution is diluted to 25.00 mL?

0.910 M

300

Given these values of ΔH° in the table, what is the value of ΔH° for the reaction?
CS2(l) + 6H2O2(l) -> CO2(g) + 6H2O(l) + 2SO2(g)

-----------------------------------------------------------
CS2(l) + 3O2(g)-> CO2(g) + 2SO2(g) ΔH°=-1077kJ/mol

H2(g) + O2(g) -> H2O2(l)   ΔH°=-188kJ/mol

H2(g) + 1/2 O2(g) -> H2O(l)    ΔH°=-286kJ/mol

-1665kJ/mol

300

Arrange CsBr, NaCl, and RbBr in increasing magnitude of lattice energy.

CsBr<RbBr<NaCl

300

What is the energy of a photon with a wavelength () of 656nm?

3.03*10-19J

400

Which is an example of an oxidation-reduction reaction?

a) HCl(aq) + RbOH(aq) -> H2O(l) + RbCl (aq)

b) (NH4)2CO3(s) -> 2NH3(g) + CO2(g) + H2O(g)

c) Pb(NO3)2(aq) + Na2SO4(aq) -> PbSO4(s) + 2NaNO3(aq)

d) Pb(s) + PbO2(s) + 2H2SO4(aq) -> 2PbSO4(s) + H2O(l)


What is   Pb(s) + PbO2(s) + 2H2SO4(aq) -> 2PbSO4(s) + H2O(l)   ?

400

What is the concentration of the bromide ion if 25.0 mL of a 0.50 M AlBr3 solution combines with 40.0 mL of a 0.35 M NaBr solution? Assume volumes are additive. 

0.79 mol/L

400

Use the given heats of formation to calculate the enthalpy change for this reaction.
B2O3(g) + 3COCl2(g) -> 2BCl3(g) + 3CO2(g)

ΔH°f: kJ/mol
B2O3(g)      -1272.8
COCl2(g)     -218.8
BCl3(g)       -403.8
CO2(g)        -393.5

-58.9kJ/mol

400

What is the hybridization of the indicated nitrogen atoms?

A: sp2

B: sp3

400

Which electronic transition in a hydrogen atom is associated with the largest emission of energy?

A) n=2 to n=1
B) n=2 to n=3
C) n=2 to n=4
D) n=3 to n=2

A) n=2 to n=1

500

What are the oxidizing agent and reducing agent in this reaction? Molecule, not ion.

Cu(NO3)2(aq) + 2V(NO3)2(aq) -> Cu(s) + 2V(NO3)4(aq)

OXIDIZING AGENT: Cu(NO3)2

REDUCING AGENT: V(NO3)2

500

What volume of 0.200 M K2C2O4 is required to react completely with 30.0 mL of 0.100 M Fe(NO3)3?

2Fe(NO3)3 + 3K2C2O4 -> Fe2(C2O4)3 + 6KNO3

22.5 mL

500

Iron can be converted to Fe2O3 according to the reaction below. How much heat (in kJ) is required to convert 10.5g of iron to Fe2O3?

2Fe(s) + 3CO(g) -> Fe2O3(s) + 3CO2(g) ΔH=26.8kJ/mol

2.52kJ

500

Using the MO diagram given to the right, what is the bond order for [N2]-?

2.5

500

What is the equation for the electron affinity of chlorine?

Cl(g) + e- -> Cl-(g)