1）In which of the following liquids do the intermolecular forces include dipole-dipole forces?
2)Which of the following best helps explain why an increase in temperature increases the rate of a chemical reaction?
A.At higher temperatures, reactions have a lower activation energy.
B.At higher temperatures, reactions have a higher activation energy.
C.At higher temperatures, every collision results in the formation of product.
D.At higher temperatures, high-energy collisions happen more frequently.
3)A sample of a hard, solid binary compound at room temperature did not conduct electricity as a pure solid but became highly conductive when dissolved in water. Which of the following types of interactions is most likely found between the particles in the substance?
1）A student investigates the enthalpy of solution, ΔHsoln, for two alkali metal halides, LiCl and NaCl. In addition to the salts, the student has access to a calorimeter, a balance with a precision of ±0.1g, and a thermometer with a precision of ±0.1°C.
a.To measure ΔHsoln for LiCl, the student adds 100.0g of water initially at 15.0°C to a calorimeter and adds 10.0g of LiCl(s), stirring to dissolve. After the LiCl dissolves completely, the maximum temperature reached by the solution is 35.6°C.
To explain why ΔHsoln for NaCl is different than that for LiCl, the student investigates factors that affect ΔHsoln and finds that ionic radius and lattice enthalpy (which can be defined as the ΔH associated with the separation of a solid crystal into gaseous ions) contribute to the process. The student consults references and collects the data shown in the table below.
(b) Write the complete electron configuration for the Na+ ion in the ground state.
(c) Using principles of atomic structure, explain why the Na+ ion is larger than the Li+ ion.
(d) Which salt, LiCl or NaCl, has the greater lattice enthalpy? Justify your answer.
(e) Below is a representation of a portion of a crystal of LiCl. Identify the ions in the representation by writing the appropriate formulas ( Li+ or Cl–) in the boxes below.
(f) The lattice enthalpy of LiCl is positive, indicating that it takes energy to break the ions apart in LiCl. However, the dissolution of LiCl in water is an exothermic process. Identify all particle-particle interactions that contribute significantly to the dissolution process being exothermic. For each interaction, include the particles that interact and the specific type of intermolecular force between those particles.