A 20mL sol'n was composed of .20M NH3 and .25 M NH4Cl

a) determine the sol'n pH (ka= 5.6 x 10^-10

b) determine the pH after 1.00mL of 1.00M HCl was added

Consider the following reaction:
Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq)
A solution is made containing an initial [Fe3+] of 1.1×10⁻³ M and an initial [SCN−] of 8.2×10⁻⁴ M. At equilibrium, [FeSCN2+]= 1.8×10⁻⁴ M .

Part A

Calculate the value of the equilibrium constant (Kc).

Express your answer using two significant figures.

Kc=

The following mechanism has been proprosed;

i.HNO2+H+<--->H2O+NO+ (fast k1)

ii. NH4+<-->NH3+H+ (fast k2)

iii. NO+ + NH3-->NH3NO+ (slow k3)

iv. NH3NO+--> H2O+H++ N2

a.Write the net overall equation?

b.The NH4+ ion is acting as the _______ in the reaction ?

c. the NO+ ion is acting as the _____ in the reaction?

d. The NH3 molecule is acting as the _____ in the reaction?

e. The H+ ion is acting as the _____ in the reaction?

f. Write the rate law for the rate determining step?

g. Write the rate law for the overall reaction?

A 115.0 −mL sample of a solution that is 2.6×10−3 M in AgNO3 is mixed with a 220.0 −mL sample of a solution that is 0.14 M in NaCN. A complex ion forms. After the solution reaches equilibrium, what concentration of Ag+(aq) remains?

how are aerobic and anaerobic decomposition, BOD, dissolved oxygen concentration, and eutropication are related to each other and what does each term means

What is the minimum mass of potassium carbonate that must be added to 100.0 mL of a 0.235 M solution of silver(I) nitrate in order to form a precipitate?

Suppose 20.0 mL of a 0.100 M NH3 solution is titrated with 0.100 M HI. Determine the pH of the solution after the addition of the following volumes of titrant.

a. 5.00 mL

b. 10.00 mL

c. 15.00 mL

d. 20.00 mL

e. 25.00 mL

Suppose that the microwave radiation has a wavelength of 12.4 cm . How many photons are required to heat 205 mL of coffee from 25.0 ∘C to 62.0 ∘C? Assume that the coffee has the same density, 0.997 g/mL , and specific heat capacity, 4.184 J/(g⋅K) , as water over this temperature range.

The Ka of a monoprotic weak acid is 5.55x10-3. what is the percent ionization of a .182 M solution of this acid

Consider a weak acid-strong base titration in which 25 mL of 0.120 M of acetic acid is titrated with 0.120 M of NaOH.

a) Calculate the pH of the acetic acid solution BEFORE addition of NaOH (pKa of acetic acid = 4.75).

b) Calculate the pH after the addition of 3.00 mL of NaOH.

c) Calculate the pH after the additon of 12.5 mL of NaOH. Notice that this is the half neutralizatiom point: some of the acetic acid molecules are converted to acetate ions producing a buffer whose pH depends on the base/acid ratio (CH3COO-/CH3COOH).

d) Calculate the pH after the addtion of 25 mL of NaOH (equivalence point).

e) Calculate the pH after the addition of 35 mL of NaOH.

f) suggest an indicator other then phenolphthalein that would be suitable for this titration and explain why.

Thank you very much.

At a certain temperature, this reaction establishes an equilibrium with the given equilibrium constant Kc.

3A + 2B -><- 4C kc=1.33x10^27

If at this temperature, 2.00 mol of A and 3.80 mol of B are placed in a 1.00L container, what are the concentrations of A, B, C at equilibrium?

Calculate the max # of moles and grams of H2S that can form when 143 g aluminum sulfide reacts with 128.8 g water?

a) ____mol H2S b) _____g H2S c) ____g excess reactant

Calculate the pH at the equivalence point in titrating 0.120 M solutions of each of the following with 9.0×10−2 MNaOH.

Part A

hydrobromic acid (HBr)

Part B

chlorous acid (HClO2)

Part C

benzoic acid (C6H5COOH)

Calculating the packing fraction (The percent space occupied by atom) for a hexagonal unit cell requires a bit more trigonometry than the same calculation for a cubic cell. However, based on your observations, which of the cubic cells would you expect to have the same packing fraction as the hexagonal cell? Explain your reasoning?

what effect would each of the following errors have on the determined concentration of the unknown acid? (would the calculated value be too high, too low, or unchanged? a) the mass of oxalic acid was recorded too low. b) the unknown acid was added to a flask containing 10 mL of water. c) the initial volume in the standardization was recorded too high. d) the initial volume in the determination of the unknown was recorded too high.