1) Which 0.1 M solution of the following acids has the highest pH

a) nitrous acid
b) ethanoic acid
c) methanoic acid
d) hypobromous acid

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2) Write an equation for the reaction of methanoic acid and water

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3) Write an equilibrium expression for the acidity constant, K_a for the reaction in 2) above

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4) A solution is prepared by adding 0.500 mol of methanoic acid, HCOOH, and 0.100 mol of sodium methanoate, HCOONa, to 2.00 L of water.
Determine the concentration of H₃O⁺ ions in this solution.
In your calculations assume that
- the equilibrium concentration of HCOOH is approximately equal to the initial concentration of HCOOH.
- the equilibrium concentration of HCOO^- is approximately equal to the initial concentration of HCOO^-

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5) Calculate the pH of this solution

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6) The following two solutions are prepared

- Solution A: 1.00 L solution contains 0.500 mole of methanoic acid.
- Solution B: 1.00 L solution contains 0.500 mole of methanoic acid and 0.100 mole of sodium methanoate.

Which solution has the higher pH? Justify your answer in terms of the equilibria involved.
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