Consider the reaction: FeS(s) + 2HCl (aq) --> FeCl2(aq) + 2H2S(g). A 4.00g sample of FeS containing nonsulfuide impurities reacted with HCl to give 896mL of H2S at 14C and 782 mmHg.Calculate mass percent purity of the sample. State your final answer using 3 Sig figs

Equilibrium constants at 25 ?C are listed in the table below.

A 360.0 −mL buffer solution is 0.170 M in HF and 0.170 M in NaF.

A) What mass of NaOH could this buffer neutralize before the pH rises above 4.00?

B) If the same volume of the buffer was 0.360 M in HF and 0.360 M in NaF, what mass of NaOH could be handled before the pH rises above 4.00? I keep getting 1.8 g and 3.5 g, which is wrong.

50.00ml of a saturated solution of calcium hydroxide is titrated with (5.00 x 10^-2 M) HNO₃. The endpoint is reached when 24.40ml of the acid is added. What is the molarity and solubility (grams/liter of solution) of the Ca(OH)₂ solution?

Thank you

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What is the theoretical yield (in g of precipitate) when 15.8 mL of a 0.572 M solution of iron(III) chloride is combined with 16.8 mL of a 0.687 M solution of lead(II) nitrate?

Air at 38.0°C and 99.0% relative humidity is to be cooled to 16.0°C and fed into a plant area at a rate of 510.0 m³/min. You may assume that the air pressure is 1 atm in all stages of the process.

Calculate the rate the water condenses in kg/min.

Question

Methane gas (CH4) enters a home heating furnace operating at steady state and burns completely with 110% of theoretical dry air, each stream entering at 77 F, 1 atm. Combustion products are discharged to the flue at 300 F, 1 atm. Return air from the house enters at 60 F, 1 atm, with a volumetric flow rate of 1000 ft3 /min and is supplied to heat the house at 120 F, 1 atm. Kinetic and potential energy effects can be neglected as can stray heat loss from the outside of the furnace to its surroundings. Determine required the fuel flow rate, in lbmol/s

Zn|Zn2+(1.00M)|| UO22+(1.00M), U4+(0.1M), H3O+(1.00M) |Pt

a) Calculate the potential in the following cell (no current is flowing)

b) The cathode has a volume of 50 mL. What is the cell potential (no current) after adding 10 mL, 25 mL, 50 mL, and 100 mL 1M NaOH to the cathode?

c) What is the Gibbs Free Energy for the 5 cells in a) and b). What is the spontaneous reaction in each case?

Are the following statements true or false?

1. A double bond consists of two pairs of electrons.

2. Side-to-side overlap results in a bond with electron density above and below the bond axis.

3. One sigma bond and one pi bond comprise a double bond.

4. A triple bond consists of one pi bond and two sigma bonds.

5. A pi bond restricts rotation about the sigma bond axis.

6. Bonds formed from atomic p orbitals can be either sigma or pi bonds.

A voltaic cell is constructed that uses the following reaction and operates at 298 K. Zn(s) + Ni2+(aq) Zn2+(aq) + Ni(s) (a)

What is the emf of this cell under standard conditions?______ V

(b) What is the emf of this cell when [Ni2+] = 2.24 M and [Zn2+] = 0.112 M?_____ V

(c) What is the emf of the cell when [Ni2+] = 0.298 M and [Zn2+] = 0.925 M?____ V

The pKb values for the dibasic base B are pKb1 = 2.10 and pKb2 = 7.32. Calculate the pH at each of the following points in the titration of 50.0 mL of a 0.80 M B(aq) with 0.80 M HCl(aq).

(a) before addition of any HCl

(b) after addition of 25.0 mL of HCl

(c) after addition of 50.0 mL of HCl

(d) after addition of 75.0 mL of HCl

(e) after addition of 100.0 mL of HCl

13. Construct energy-level diagrams for both high- and low-spin situations for the d6 electron configuration in (a) an octahedral field; (b) a tetrahedral field.

Please explain if possible...I do understand the orbital principle generally. Thank you.

Which method, UPS or XPS, is better for resolving chemical shifts and why? Which direction would a peak in a given spectrum move if an atom loses a valence charge? What if the atom gains a valence charge? Does the kinetic energy of the photoelectron depend on the X-ray or UV beam energy?

Classify each statement as applying to osmosis, dialysis, or both osmosis and dialysis. Be sure to place all statements. Note: If any part of this question is answered incorrectly, a single red X will appear indicating that one or more of the phrases has been placed incorrectly.

-involves the movement of water across a semipermeable membrane

-may be used as a way to seperate small molecules and ions from colloids

-involves the movement of small particles across a semipermeable membrane

-involves the movement of water across a cell membrane.

-can be used medically in artificial kidney machines to remove urea.