Distilled water frequently contains dissolved CO_2, mating the pH different from the theoretical value for pure water. Would Bus cause the pH of your buffer to be slightly higher or slightly lower than the target pH? Explain Was the pH of the buffer you prepared slightly higher or slightly lower than the target value? The pH of a buffer can be adjusted by added small amounts of HCl or NaOH When of these should be added to your buffer to remedy the problem identified in (a)? Defend your choice. Consider the HClO/ClO conjugate acid/base pair. Consult your text or other source for appropriate acid dissociation constants. The hypochlorite ion is the active ingredient in bleach. NaCIO(aq) Explain why this acid/base pair would be a candidate for a buffer with pH = 7.3 (approximate physiological value). Based on your advice in (a), a researcher used this very buffer in a growth medium (including appropriate food and temperature control) for bacteria that proliferate at physiological pH DE sprite the carefully prepared medium. however, bacterial growth was dismal Explain. Biochemists frequently use -phosphate' buffers in their work. Here, 'phosphate' refers generally to the class of phosphate derived ions: H_2PO_4 HPO_4 PO Which of these ions best represents the conjugate acid in a 'phosphate* buffer at physiological pH? Explain. A buffer used in an experiment was described as 'a 02 M phosphate buffer with pH = 7.25.' Based on the conjugate and you identified in (a), determine the concentration of conjugate acid to this '0.2 M phosphate buffer "
a high concentration of conjugate acid molecules in solution and the pH of the solution
an equal number of conjugate acid and base molecules, and a high concentration of each
how close the buffer is to having a 10:1 ratio of the buffer components, and having a high concentration of the components
the range of pH values over which the solution can act as a buffer, and an equal ratio of conjugate acid to conjugate base
6)
A 1.0-L buffer solution is 0.120 M in HNO2 and 0.160 M in NaNO2.
Part A
Determine the concentrations of HNO2 and NaNO2 after addition of 1.7 g HCl.
Express your answers using three significant figures separated by a comma.
Part B
Determine the concentrations of HNO2 and NaNO2 after addition of 1.7 g NaOH.
Express your answers using three significant figures separated by a comma.
Part C
Determine the concentrations of HNO2 and NaNO2 after addition of 1.7 g HI.
Express your answers using three significant figures separated by a comma.
7)
Why is the molar solubility of silver chloride lower in an aqueous solution of sodium chloride than in pure water?
Why is the molar solubility of silver chloride lower in an aqueous solution of sodium chloride than in pure water?
because the presence of extra chloride ion shifts the equilibrium of the AgCl dissolution reaction toward the undissociated silver chloride
because solubility relies on concentrations of all the species in the dissolution reaction equation, and lower solubility means higher amounts of solid silver chloride
because silver ions and sodium ions form a completely insoluble precipitate and fall out of the solution
because sodium chloride takes up all the water and doesn't leave any interactions for the silver chloride, causing reduced solubility
8)
In which of the following would lead sulfate be most soluble?
In which of the following would lead sulfate be most soluble?