Author: Anonymous

If 10.1 g of naphthalene, C 10H 8, is dissolved in 105.0 g of chloroform, CHCl 3, what is the molality of the solution?

The concentration of H 3O + in a solution is 4  × 10 –4 M at 25°C. What is its hydroxide-ion concentration?  Note: Written work required Hint: Kw = 1.01 × 10–14

Which equation depicts the hydrogen phosphate ion (HPO 4 2–) behaving as a Brønsted –Lowry base in water?

Consider the reaction NH 3( aq) + H 2O( l) NH 4 +( aq) + OH –( aq). K b for NH 3 is 1.8  × 10 –5 at 25°C. What is Ka for the NH 4 + ion at 25°C? Note: Written work required Hint: Kw = 1.0 x 10-14

For a monoprotic acid titration, the _____ in a titration is the point where number of moles of a strong base added equals the number of moles of an acid initially present.

What is the pH at the equivalence point when a 25.0 mL sample of 0.200 M aqueous formic acid (HCO 2H) is titrated with 0.100 M aqueous potassium hydroxide? ( K a of HCO 2H = 1.8 × 10 –4) Note: Written work required Hint: Weak acid + strong base titration problem

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What is the hydronium-ion concentration of a 0.30 M solution of HCN ( Ka = 4.9  × 10 –10) at 25°C? Note: Written work required Hint: ICE table required

What is the equilibrium pH of an initially 0.69 M solution of the monoprotic acid benzoic acid at 25°C ( Ka =  )? Note: Written work required Hint: ICE table required

The pH of a solution at 25 °C in which [OH –] = 3.2 × 10 –5 M is _____. ( K w = 1.01 × 10 –14) Note: Written work required