State whether each of the following statements is true or false. Justify your answer in each case.
(a) When methanol, \(\mathrm{CH}_{3} \mathrm{OH}\), is dissolved in water, a conducting solution results.
(b) When acetic acid, \(\mathrm{CH}_{3} \mathrm{COOH}\), dissolves in water, the solution is weakly conducting and acidic in nature.
Text Transcription:
CH_3OH
CH_3COOH
Step 1 of 5) When methanol, CH3OH, is dissolved in water, a conducting solution results.When acetic acid, CH3COOH, dissolves in water, the solution is weakly conducting and acidic in nature.When a student mixes 50 mL of 1.0 M HCl and 50 mL of 1.0 M NaOH in a coffee-cup calorimeter, the temperature of the resultant solution increases from 21.0 to 27.5 °C. Calculate the enthalpy change for the reaction in kJ>mol HCl, assuming that the calorimeter loses only a negligible quantity of heat, that the total volume of the solution is 100 mL, that its density is 1.0 g>mL, and that its specific heat is 4.18 J>g@K.Bomb Calorimetry (Constant-Volume Calorimetry) An important type of reaction studied using calorimetry is combustion, in which a compound reacts completely with excess oxygen. (Section 3.2) Combustion reactions are most accurately studied using a bomb calorimeter (Figure 5.19). The substance to be studied is placed in a small cup within an insulated sealed vessel called a bomb. The bomb, which is designed to withstand high pressures, has an inlet valve for adding oxygen and electrical leads for initiating the reaction. After the sample has been placed in the bomb, the bomb is sealed and pressurized with oxygen. It is then placed in the calorimeter and covered with an accurately measured quantity of water. The combustion reaction is initiated by passing an electrical current through a fine wire in contact with the sample. When the wire becomes sufficiently hot, the sample ignites.
