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The maximum safe concentration of fluoride ion in drinking water is \(2.0\) ppm (parts per million). Express this concentration in milligram \(\%\).

A household cleaning solution has a hydronium ion concentration of \(10^{-11} \mathrm{M}\). What is the \(\mathrm{pH}\) of the solution? Is the solution acidic or basic?

10 cc of battery acid (density \(1.21\) ) is diluted to 100 cc. \(30 \mathrm{cc}\) of the dilute solution is neutralized by \(45 \mathrm{cc}\) of \(0.5 \mathrm{~N}\) base. What is the normality of the diluted acid? What is its strength in grams per liter? What is the strength of the undiluted \(1.21\) density acid in \(\mathrm{g} / \ell\) ?

Calculate the osmotic work done by the kidneys in secreting \(0.158\) moles of \(\mathrm{Cl}^{-}\) in a liter of urine water at \(37^{\circ} \mathrm{C}\) when the concentration of \(\mathrm{Cl}^{-}\) in plasma is \(0.104 \mathrm{M}\), and in urine \(0.158 \mathrm{M}\)

A \(25.00-\mathrm{ml}\) sample of sea water is titrated with \(2.50 \mathrm{M}\) \(\mathrm{AgN} 0_{3}\) solution, using \(\mathrm{K}_{2} \mathrm{CrO}_{4}\), as an indicator, until the presence of excess \(\mathrm{Ag}^{+}\) is shown by the reddish color of \(\mathrm{Ag}_{2} \mathrm{CrO}_{4}\) at the end point. The density of the sea water is \(1.028 \mathrm{~g} / \mathrm{cc}\). Find the chlorinity and salinity of the sea water if \(53.50 \mathrm{ml}\) of \(\mathrm{AgNO}_{3}\) solution were used to complete the precipitation of silver halides.

Hard water is often softened by a commercial water softener. Explain, in general, its operation.

Hydrogen chloride (HC1) is used industrially in the manufacture of fabric dyes. The acidic properties of \(\mathrm{HCl}\) arise because the \(\mathrm{H}-\mathrm{Cl}\) bond is polar. The observed dipole moment, \(\mathrm{u}_{\text {obs }}\) of \(\mathrm{HCl}\) is \(1.03 \mathrm{D}\) and the \(\mathrm{H}-\mathrm{Cl}\) bond distance is \(1.28 \AA\). Estimate the percent ionic character of the \(\mathrm{HCl}\) bond. Electron charge, \(\mathrm{e}=4.8 \times 10^{-18}\) esu.