91Ó°ÊÓ

Calculate the molar masses of the following substances: \- \(\mathrm{NaBr}\) : \- \(\mathrm{SrCl}_2\) : \- \(\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6\) :

Label the following solutions as electrolytes or nonelectrolytes: (Note: Assume these compounds are all in aqueous solution.) $$ \begin{array}{|l|l|l|} \hline \text { - } \mathrm{HCl} & \text { Electrolyte } & \text { Nonelectrolyte } \\ \hline \text { - Sucrose } & \text { Electrolyte } & \text { Nonelectrolyte } \\\ \hline \text { - } \mathrm{MgBr}_2 & \text { Electrolyte } & \text { Nonelectrolyte } \\ \hline \text { - } \mathrm{CH}_4 & \text { Electrolyte } & \text { Nonelectrolyte } \\ \hline \end{array} $$

What are some similarities and differences between molecular and empirical formulas? \- Similarities: \- Differences:

Identify the following ions as cations or anions, and then provide the formula or chemical symbol: $$ \begin{array}{|l|l|l|} \hline {\text { Ion }} & \text { Cation or Anion } & \text { Formula } \\ \hline \text { Phosphate } & & \\ \hline \text { Hypochlorite } & & \\ \hline \text { Ammonium } & & \\ \hline \text { Phosphide } & & \\ \hline \text { Bicarbonate } & & \\ \hline \text { Nitrite } & & \\ \hline \text { Chromium(II) } & & \\ \hline \end{array} $$

If \(46 \mathrm{~g} \mathrm{Na}\) and \(32 \mathrm{~g} \mathrm{O}_2\) are provided, find the maximum number of moles of sodium oxide produced.

How do the number of molecules in \(18 \mathrm{~g}\) of \(\mathrm{H}_2 \mathrm{O}\) compare to the number of formula units in \(58.5 \mathrm{~g}\) of \(\mathrm{NaCl}\) ?

Experimental data from the combustion of an unknown compound indicates that it is \(28.5 \%\) iron, \(24.0 \%\) sulfur, and \(49.7 \%\) oxygen by mass. What is its empirical formula?

\(\mathrm{Be}(\mathrm{OH})_2\) is produced when water reacts with \(\mathrm{BeO}\). Starting with \(2.5 \mathrm{~kg} \mathrm{BeO}\) in excess water, and producing \(1.1 \mathrm{~kg} \mathrm{Be}(\mathrm{OH})_2\), what is the percent yield of this reaction?