CHEM 1011 MIDTERM COMPETENCY REVIEW
2026 MOCK TEST COMPLETE KEY INSIGHTS
◉ Determine state of CO2 at 400*C and 300 atm (pic on next page).
Answer: Supercritical fluid (SCF)
◉ Metallic solids:
-are composed of positive and negative ions held together by
electrostatic attractions
-are composed of atoms, with nuclei in a "sea" of delocalized
electrons
-are composed of atoms held together by a repeating network of
covalent bonds
-are composed of neutral molecules held together by intermolecular
forces.
Answer: are composed of atoms, with nuclei in a "sea" of delocalized
electrons
◉ Acetonitrile, CH3CN, is a common solvent used in organic
chemistry labs. Acetonitrile evaporates very quickly at room
temperature and feels noticeably cold when evaporating. If the
ΔHvap for acetonitrile is 34.2 kJ/mol, how much heat is removed
when 2.3 g of acetonitrile evaporates?
,1.92 kJ
2.76 kJ
3.23 kJ
0.362 kJ.
Answer: 1.92 kJ
◉ A solution
-is always homogeneous
-always has a solvent and solute in the same physical state
-can spontaneously separate into solute particles and solvent
-is always formed from a solid dissolved into a liquid.
Answer: is always homogenous
◉ When a solute is introduced to a solvent
-energy is required to overcome solute-solute and solvent-solvent
interactions
-energy is required when solute-solvent interactions are formed
-a solution will always form
-a solution will only form if the energy released by solvation is
minimal.
, Answer: energy is required to overcome solute-solute and solvent-
solvent interactions
◉ Strong electrolytes
-dissociate nearly completely into ions in solution
-only yield a small fraction of ions in solution
-are always a dissolved ionic compound
-cannot be covalent compounds.
Answer: dissociate nearly completely into ions in solution
◉ Which of the following will have the lowest conductivity when
dissolved in water?
-0.1 M potassium chloride, KCl
-0.1 M sodium sulfate, Na2SO4
-0.1 M Calcium nitrate, Ca(NO3)2
-0.1 M sucrose, C12H22O11.
Answer: 0.1 M sucrose, C12H22O11
◉ The solubility of a solid in a liquid
-always increases with increasing temperature
-typically increases with increasing temperature, with a few
exceptions
2026 MOCK TEST COMPLETE KEY INSIGHTS
◉ Determine state of CO2 at 400*C and 300 atm (pic on next page).
Answer: Supercritical fluid (SCF)
◉ Metallic solids:
-are composed of positive and negative ions held together by
electrostatic attractions
-are composed of atoms, with nuclei in a "sea" of delocalized
electrons
-are composed of atoms held together by a repeating network of
covalent bonds
-are composed of neutral molecules held together by intermolecular
forces.
Answer: are composed of atoms, with nuclei in a "sea" of delocalized
electrons
◉ Acetonitrile, CH3CN, is a common solvent used in organic
chemistry labs. Acetonitrile evaporates very quickly at room
temperature and feels noticeably cold when evaporating. If the
ΔHvap for acetonitrile is 34.2 kJ/mol, how much heat is removed
when 2.3 g of acetonitrile evaporates?
,1.92 kJ
2.76 kJ
3.23 kJ
0.362 kJ.
Answer: 1.92 kJ
◉ A solution
-is always homogeneous
-always has a solvent and solute in the same physical state
-can spontaneously separate into solute particles and solvent
-is always formed from a solid dissolved into a liquid.
Answer: is always homogenous
◉ When a solute is introduced to a solvent
-energy is required to overcome solute-solute and solvent-solvent
interactions
-energy is required when solute-solvent interactions are formed
-a solution will always form
-a solution will only form if the energy released by solvation is
minimal.
, Answer: energy is required to overcome solute-solute and solvent-
solvent interactions
◉ Strong electrolytes
-dissociate nearly completely into ions in solution
-only yield a small fraction of ions in solution
-are always a dissolved ionic compound
-cannot be covalent compounds.
Answer: dissociate nearly completely into ions in solution
◉ Which of the following will have the lowest conductivity when
dissolved in water?
-0.1 M potassium chloride, KCl
-0.1 M sodium sulfate, Na2SO4
-0.1 M Calcium nitrate, Ca(NO3)2
-0.1 M sucrose, C12H22O11.
Answer: 0.1 M sucrose, C12H22O11
◉ The solubility of a solid in a liquid
-always increases with increasing temperature
-typically increases with increasing temperature, with a few
exceptions
