CHEM 219 LAB EXAMS 1 TO 4 COMBINED
ACTUAL QUESTIONS AND CORRECT
ANSWERS
◉ graduated cylinder.
Answer: instrument used to measure volume of a liquid
◉ Buret.
Answer: Used in titration to measure precisely how much liquid is
used.
◉ Magnetic stir bar.
Answer: small white oblong Teflon-covered magnet, used to stir
solutions when placed on a stir motor
◉ clamp.
Answer: surgical instrument used to compress blood vessel or close
off end of intestine
◉ ring stand.
Answer: holds funnels, wire gauze above table
,◉ spot plate.
Answer: a flat plate with multiple "wells" used as small test tubes
◉ squirt bottle.
Answer:
◉ test tube.
Answer: open tube used to hold liquids
◉ stir rod.
Answer: Mixing substances
◉ vial.
Answer: small bottle containing medicine or other liquids
◉ syringe.
Answer: a medical instrument used to inject or withdraw fluids
◉ Bunsen Burner safety.
Answer: -Do not keep gas on while burner is not in use
-Always keep watch of the burner and never direct towards people
-Keep area around burner clear
,-Don't burn flammable liquids
◉ Chemical Safety.
Answer: -Any waste with special instructions for disposal will be
placed in a container in the fume hood
-In redox reactions the reducing agent and oxidizing agent must be
disposed of separately
-Concentrated HCl produces vapors and should be used in the fume
hood
-Mg reacts with acid and produces hydrogen gas, this is flammable
-Silver nitrate may cause dark spots on skin
◉ Centrifuge use.
Answer: -Do not put stoppers in vials
-Place equal amounts of liquid on opposite sides of the rotor
-Centrifuging does not require much time
-Ensure lid is closed and safety switch is engaged
-Do not place hand in rotor while rotor is moving
◉ Balance use.
Answer: -Tare before massing
-Do not place extra material into container, dispose of it properly
, -Use the spatula to move material
◉ Color wheel.
Answer: -The light absorbed is opposite of the light transmitted
(seen)
-𝜆 = wavelength
-𝜈 = frequency
◉ Thermodynamics.
Answer: ΔG=ΔH-TΔS
+ΔH = endothermic
-ΔH = exothermic
-Entropy (ΔS) increases with increasing number of configurations
-Solid < liquid << gas
◉ Equilibrium.
Answer: aA + bB -> cC + dD
K = [A]^a [B]^b/ [C]^c [D]^d
-Le Chatelier's principle
-Away from an increase towards a decrease
◉ Acid/base.
ACTUAL QUESTIONS AND CORRECT
ANSWERS
◉ graduated cylinder.
Answer: instrument used to measure volume of a liquid
◉ Buret.
Answer: Used in titration to measure precisely how much liquid is
used.
◉ Magnetic stir bar.
Answer: small white oblong Teflon-covered magnet, used to stir
solutions when placed on a stir motor
◉ clamp.
Answer: surgical instrument used to compress blood vessel or close
off end of intestine
◉ ring stand.
Answer: holds funnels, wire gauze above table
,◉ spot plate.
Answer: a flat plate with multiple "wells" used as small test tubes
◉ squirt bottle.
Answer:
◉ test tube.
Answer: open tube used to hold liquids
◉ stir rod.
Answer: Mixing substances
◉ vial.
Answer: small bottle containing medicine or other liquids
◉ syringe.
Answer: a medical instrument used to inject or withdraw fluids
◉ Bunsen Burner safety.
Answer: -Do not keep gas on while burner is not in use
-Always keep watch of the burner and never direct towards people
-Keep area around burner clear
,-Don't burn flammable liquids
◉ Chemical Safety.
Answer: -Any waste with special instructions for disposal will be
placed in a container in the fume hood
-In redox reactions the reducing agent and oxidizing agent must be
disposed of separately
-Concentrated HCl produces vapors and should be used in the fume
hood
-Mg reacts with acid and produces hydrogen gas, this is flammable
-Silver nitrate may cause dark spots on skin
◉ Centrifuge use.
Answer: -Do not put stoppers in vials
-Place equal amounts of liquid on opposite sides of the rotor
-Centrifuging does not require much time
-Ensure lid is closed and safety switch is engaged
-Do not place hand in rotor while rotor is moving
◉ Balance use.
Answer: -Tare before massing
-Do not place extra material into container, dispose of it properly
, -Use the spatula to move material
◉ Color wheel.
Answer: -The light absorbed is opposite of the light transmitted
(seen)
-𝜆 = wavelength
-𝜈 = frequency
◉ Thermodynamics.
Answer: ΔG=ΔH-TΔS
+ΔH = endothermic
-ΔH = exothermic
-Entropy (ΔS) increases with increasing number of configurations
-Solid < liquid << gas
◉ Equilibrium.
Answer: aA + bB -> cC + dD
K = [A]^a [B]^b/ [C]^c [D]^d
-Le Chatelier's principle
-Away from an increase towards a decrease
◉ Acid/base.
