CHM 113 FINAL QUIZ & ANSWERS 100% CORRECT

CHM 113 FINAL QUIZ & ANSWERS
100% CORRECT
[C&GDBaSO₄] The drop must fall through the drop counter in the exact center. -
ANSWERTrue.

[C&GDBaSO₄] What is the unit of conductometry? - ANSWERµS/cm (microsiemens
per cm)

[C&GDBaSO₄] What shape will a titration curve have? - ANSWER

[C&GDBaSO₄] Why do we need to flocculate to ensure complete precipitation? -
ANSWER

[C&GDBaSO₄] Give the chemical formula of the precipitate formed at the end of the
precipitation reaction. - ANSWER

[C&GDBaSO₄] What does gravimetric analysis depend upon? - ANSWERmass

[C&GDBaSO₄] Differentiate between quantitative and qualitative analysis. -
ANSWERQuantitative: how much is present, qualitative: what is present
[Acids/Bases] Name 3 methods to determine pH. How do they work? Which one is
best? - ANSWER

[Acids/Bases] What gas is dissolved in soda to form H₂CO₃ in a soft drink? -
ANSWER

[Acids/Bases] What will happen if you boil cabbage for too long? - ANSWER

[Acids/Bases] If the pH of a solution is 9.3 what is the [OH⁻]? - ANSWER

[FPDLA] What happens to the freezing point of a solution when solute is added?
Why? - ANSWERThe freezing point will go down because adding solute will lower
the temperature, which in turn lowers the freezing point.

[FPDLA] Freezing point is directly proportional to which quantity/quantities? -
ANSWER

[FPDLA] Why is molality used to calculate freezing point depression instead of
molarity? - ANSWERMolarity changes due to temperature changes while molality
doesn't, making molality the preferred calculation


[C&GDBaSO₄] Write the balanced equation of the reaction during titration and
determine the state of each substance in the equation. - ANSWER

, [C&GDBaSO₄] What is equivalence point? - ANSWERthe volume when the
conductivity value reaches a minimum

[C&GDBaSO₄] What are the requirements for gravimetric analysis to work? -
ANSWERThe sample must be pure with no contamination and of known
stoichiometry; the sample must be dry; the solid that is precipitated should be in the
form of reasonably large, well formed crystals; the % yield should be 99.9% or better;
interference by other types of compounds forming precipitates should be minimal;
the MW of the precipitated solid should be high enough that a reasonable weight of
precipitate is generated.

[C&GDBaSO₄] Write the two goals of this experiment. - ANSWERTo find the
equivalence point and the unknown concentration of BaSO₄

[Safety and Density] What are the two things you cannot come to lab without? -
ANSWERSafety goggles and your lab manual

[Safety and Density] You should draw fluid into a pipette with: - ANSWERa suction

[Safety and Density] Give the definition of density and its units - ANSWERDensity is
the relationship between the mass of a substance and its volume. g/mL

[Safety and Density] Define mass and volume. Write their units. - ANSWERMass is
measured in grams and is the amount of space an object occupies. Volume is
measured in mL and is an object's length x width x height.

[Safety and Density] What temperature is water most dense at? - ANSWER4 C°

[Safety and Density] What is the density of water at 4°C? - ANSWER1 g/mL

[Safety and Density] Give an example of two extensive and intensive properties. -
ANSWERE: volume, mass; I: density, color

[Density] What is the difference between density and specific gravity? -
ANSWERDensity is mass/volume; specific gravity is density of the substance/density
of water.

[Density] What are the units of density? - ANSWERg/cm³, g/mL, g/L

[Density] What are the units of specific gravity? - ANSWERIt is unitless

[Density] Why do some things have a high density and others a low density? -
ANSWERIt depends on how the atoms of the object are. Loosely arranged atoms
lead to lower density and vice versa.

[Density] Why is density such an important physical property? - ANSWER

[Density] What is the conversion factor of cm³ to mL? - ANSWER1 cm³ = 1 mL