For which case would ΔHsoln be expected to be negative?

What is the major intermolecular force that exists between water and chloromethane (shown below)?image0016148cb1e.gif

Gold purity is measured in karats. 18 karat gold is a solution that consists of 75% gold and 25% silver by     mass. Which element is the solute in this solution?

At 500 oC cyclopropane (C3H6) rearranges to propene (CH3CHCH2) as shown by C3H6(g) –> CH3CHCH2(g).  The reaction is first-order with a half-life of 17 minutes. How long will it take for the concentration of C3H6 to drop to 12.5% of its initial value at 500 oC?

Integrated rate law plots are shown below. Match each plot (i, ii, and iii) to the order of reaction it represents. orders of reaction.JPG

Using the universal numbering system for the deciduous dentition, what is the proper identifier for the deciduous maxillary right canine?

The following set of data was obtained by the method of initial rates for the reaction:2 HgCl2(aq) + C2O42-(aq) → 2 Cl-(aq) + 2 CO2(g) + Hg2Cl2(s) Experiment Rate 1 0.10 M 0.10 M 1.3 x 10-7 M/s 2 0.10 M 0.20 M 5.2 x 10-7 M/s 3 0.20 M 0.20 M 1.0 x 10-5 M/s  What is the rate law for the reaction?

What is the vapor pressure over a solution that contains 0.850 mol CaCl2 dissolved in 27.7 mol of water at 298 K. The vapor pressure of water is 23.76 mmHg at 289 K. (HINT: Don’t forget to find total moles of ions.)

Which of the following is NOT part of the periodontium?

True or False: Together, the sulcular epithelium and the junctional epithelium form the dentogingival junctional tissue.