equal volumes of solutions of the given concentrations are mixed together. which of the resulting aqueous solutions makes a buffer?

Calculate the pH of a buffer solution prepared by dissolving 4.2 g of NaHCO3 and 5.3 g of Na2CO3 in 0.20 L of water. Will the pH change if the solution volume is increased by a factor of 10?

[13] Write the equilibrium mass balance expressions for the following equilibrium in terms of (a) KC and (b) KP.
4HCl(aq) + MnO2(s) ? Cl2(g) + 2H2O(l) + MnCl2(aq)

[14] At 700 K the rate constant for the reaction 2NO + O2 ? 2NO2 is 5.73

Malonic acid (FW = 104.06) is a diprotic acid of the form CH2(COOH)2, with pKa1 = 2.847
and pKa2 = 5.696. Assume all solutions are ideal.
(a) If 15.000 g of malonic acid is added to 100 mL of pure water, what will the pH of the
solution be?
(b) You add 18 mL of 5 M NaOH to the solution in part (a). What will the new pH be?
(c) You then add 5.000 g of sodium malonate (Na2CH2(COO), FW = 148.025). What will
the new pH be?

1. Consider a galvanic cell consisting of the following two redox couples:

            Ag⁺(0.010M) + e^- --> Ag(s)    E⁰ = +0.80 V

         Cr³⁺(0.010M) + e^- --> Cr(s)   E⁰ = -0.74 V

Write the equation for the half reaction occurring at the cathode

Write the equation for the half reaction occurring at the anode.

Write the equation for the cell

What is the standard cell potential E⁰_cell for the cell?

Realizing the nonstandard concentrations, what is the actual cell potential, E⁰_cell for the cell? What is the value of the Nernst equation

Determine the mass (in g) of Ca₃(PO₄)₂ that is produced when 140 mL of a 8.48×10^-2 M Na₃PO₄ solution completely reacts with 778 mL of a 1.54×10^-2 M CaCl₂ solution according to the following balanced chemical equation.  

2Na₃PO₄(aq) + 3CaCl₂(aq) → Ca₃(PO₄)₂(s) + 6NaCl(aq)

A gas expands from an initial volume of 4.88 L to a final volume of 6.33 L against an external pressure of 810. mmHg. During the expansion the gas absorbs 10. J of heat. What is the change in the internal energy of the gas?

An organic liquid is a mixture of methyl alcohol (CH3OH) and ethyl alcohol (C2H5OH). A 0.220-g sample of the liquid is burned in an excess of O2(g) and yields 0.347 g CO2(g) (carbon dioxide).

Set up two algebraic equations, one expressing the mass of carbon dioxide produced in terms of each reagent and the other expressing the mass of sample burned in terms of each reagent.

What is the mass of methyl alcohol (CH3OH) in the sample?

List the allowed quantum numbers m_l and m_s for the following subshells and determine the maximum occupancy of the subshells. a) 2p b) 3d c) 4f d) 5g

Write the balanced reaction equation for the precipitation of calcium carbonate from
potassium carbonate and calcium chloride. Don't forget to show the states of matter.

Using this balanced equation in the above question, determine the limiting reactant if 25 grams of calcium chloride
reacted with 25 grams of potassium carbonate. Show your work.

The freezing point of water is 0.00°C at 1 atmosphere. If 13.93 grams of manganese(II) bromide, (214.7 g/mol), are dissolved in 280.9 grams of water ...

The molality of the solution is _______ m.

The freezing point of the solution is ______ °C.

Enough of a monoprotic acid is dissolved in water to produce a 0.0103 M solution. The pH of the resulting solution is 2.53. Calculate the Ka for the acid.

I got 8.45x10^-4 but it says its wrong.

A buffer solution contains 0.14 mol of ascorbic acid (HC₆H₇O₆) and 0.84 mol of sodium ascorbate (NaC₆H₇O₆) in 2.80 L.
The K_a of ascorbic acid (HC₆H₇O₆) is K_a = 8e-05.



(a) What is the pH of this buffer?

pH =  


(b) What is the pH of the buffer after the addition of 0.07 mol of NaOH? (assume no volume change)

pH =  


(c) What is the pH of the original buffer after the addition of 0.21 mol of HI? (assume no volume change)

pH =  

Calculate the pH of a mixture that contains 0.25 M of HCOOH and 0.14 M of HClO. The Ka of HCOOH is 1.8 × 10-4 and the Ka of HClO is 4.0 × 10-8.