51CHAPTER 4 TYPES OF CHEMICAL REACTIONS AND SOLUTION STOICHIOMETRYAqueous Solutions: Strong and Weak Electrolytes10.Only statement b is true. A concentrated solution can also contain a nonelectrolyte dissolvedin water, for example, concentrated sugar water. Acids are either strong or weak electrolytes.Some ionic compounds are not soluble in water, so they are not labeled as a specific type ofelectrolyte.11.a.Polarity is a term applied to covalent compounds. Polar covalent compounds have anuneBual sharing of electrons in bonds that results in uneBual charge distribution in theoverall molecule. Polar molecules have a partial negative end and a partial positive end.These are not full charges as in ionic compounds but are charges much smaller inmagnitude. Water is a polar molecule and dissolves other polar solutes readily. Theoxygen end of water (the partial negative end of the polar water molecule) aligns with thepartial positive end of the polar solute, whereas the hydrogens of water (the partialpositive end of the polar water molecule) align with the partial negative end of the solute.These opposite charge attractions stabilize polar solutes in water. This process is calledhydration. Nonpolar solutes do not have permanent partial negative and partial positiveendsI nonpolar solutes are not stabilized in water and do not dissolve.b.KF is a soluble ionic compound, so it is a strong electrolyte. KF(aB) actually exists asseparate hydrated K+ions and hydrated F!ions in solution. C6O12O6is a polar covalentmolecule that is a nonelectrolyte. C6O12O6is hydrated as described in part a.c.RbCl is a soluble ionic compound, so it exists as separate hydrated Rb+ions and hydratedCl!ions in solution. AgCl is an insoluble ionic compound so the ions stay together insolution and fall to the bottom of the container as a precipitate.d.ONO3is a strong acid and exists as separate hydrated O+ions and hydrated NO3!ions insolution. CO is a polar covalent molecule and is hydrated as explained in part a.12.MgSO4(s)"Mg2+(aB) + SO42!(aB)INO4NO3(s)"NO4+(aB) + NO3!(aB)13.a.Ba(NO3)2(aB)"Ba2+(aB) + 2 NO3!(aB)Ipicture iv represents the Ba2+and NO3!ionspresent in Ba(NO3)2(aB).b.NaCl(aB)"Na+(aB) + Cl!(aB)Ipicture ii represents NaCl(aB).
52COAPTER 4SOLUTION STOICOIOMETRYc.K2CO3(aB)"2 K+(aB) + CO32!(aB)I picture iii represents K2CO3(aB).d.MgSO4(aB)"Mg2+(aB) + SO42!(aB)I picture i represents MgSO4(aB).Solution Concentration: Molarity 14.75.0 mL \g1.46mol1mLg79.0#^1.3 mol C2O5OOI molarity ^L250.0mol3.1^ 5.2!C2O5OO15. a.2.00 Lmolb.2.00 LNaOOmol00.1NaOOg00.40LNaOOmol250.0##^ 20.0 g NaOOPlace 20.0 g NaOO in a 2-L volumetric flaskI add water to dissolve the NaOO, and fill tothe mark with water, mixing several times along the way.stockL1LNaOOmol250.0
- Spring '08
- Stoichiometry, Trigraph, mol, mol Ag