experimental apparatus
Which apparatus is not commonly used in the chemistry lab?
a. stopwatch
b. thermometer
c. balance
d. weighing scale
weighing scale
What is the purpose of rinsing the burette with distilled water followed by the chemical solution before titration?
a) To dry the apparatus
b) To remove impurities or contaminants
c) To cool down the apparatus
d) To increase the volume of the solution
b) To remove impurities or contaminants
1. What is the purpose of the origin line in paper chromatography?
a) To mark where the solvent starts moving
b) To indicate the end of the separation process
c) To place the sample spots without interference
d) To measure the temperature of the solvent
c) To place the sample spots without interference
1. What is the main characteristic of a pure substance's melting point?
a) It changes with pressure
b) It occurs over a wide temperature range
c) It is sharp and specific
d) It cannot be measured
c) It is sharp and specific
1. What is the flame test colour for sodium ions (Na⁺)?
a) Red
b) Yellow
c) Green
d) Blue
b) Yellow
What is one disadvantage of using a mercury thermometer?
Mercury is very toxic
2. Which indicator turns from pink to colourless at the end-point in an acid-base titration?
a) Methyl orange
b) Litmus
c) Phenolphthalein
d) Universal indicator
c) Phenolphthalein
2. How is the RfRf value calculated?
a) Distance traveled by substance ÷ Distance traveled by solvent
b) Distance traveled by solvent ÷ Distance traveled by substance
c) Total volume of solvent used × Distance traveled by substance
d) Mass of the substance × Solvent density
a) Distance traveled by substance ÷ Distance traveled by solvent
2. Which method is used to separate immiscible liquids like oil and water?
a) Filtration
b) Separating funnel
c) Crystallisation
d) Simple distillation
b) Separating funnel
2. Which gas turns damp red litmus paper blue?
a) Ammonia
b) Carbon dioxide
c) Oxygen
d) Hydrogen
a) Ammonia
Which is the correct advantage of using a mercury thermometer?
a. Easy to read since it is visible and has silvery shine to it.
b. It wets the wall of glass vessel in the which it is kept.
c. It cannot measure a high temperature.
d. It measures temperature slowly.
a. Easy to read since it is visible and has silvery shine to it.
3. Why is a white tile used during titration?
a) To support the burette
b) To make colour changes more visible
c) To measure temperature
d) To store chemicals
b) To make colour changes more visible
3. Why is a pencil used instead of ink to draw the origin line?
a) Pencil marks are more visible
b) Ink would dissolve and interfere with results
c) Pencil lines help the solvent move faster
d) Ink lines absorb too much sample
b) Ink would dissolve and interfere with results
3. What remains in the filter paper after filtration?
a) Filtrate
b) Solvent
c) Residue
d) Saturated solution
c) Residue
3. What is the observation when excess NaOH is added to aluminium ions (Al³⁺)?
a) White precipitate remains
b) Green precipitate forms
c) White precipitate dissolves to form a colourless solution
d) Red-brown precipitate forms
c) White precipitate dissolves to form a colourless solution
What is the name of apparatus used to measure liquid at ranging from 0cm3 to 50cm3?
Burette
4. What colour does methyl orange show in an alkaline solution?
a) Red
b) Yellow
c) Pink
d) Colourless
b) Yellow
4. What does a single spot on a chromatogram indicate?
a) The substance is a mixture
b) The solvent was contaminated
c) The substance is pure
d) The separation was incomplete
c) The substance is pure
4. What is the purpose of cooling a saturated solution slowly during crystallisation?
a) To evaporate the solvent faster
b) To allow large, pure crystals to form
c) To dissolve impurities
d) To increase the boiling point
b) To allow large, pure crystals to form
4. Which anion produces a white precipitate with acidified barium nitrate solution?
a) Carbonate (CO₃²⁻)
b) Nitrate (NO₃⁻)
c) Sulfate (SO₄²⁻)
d) Chloride (Cl⁻)
c) Sulfate (SO₄²⁻)
Pipette
5. Which of the following is NOT a required apparatus for acid-base titration?
a) Conical flask
b) Bunsen burner
c) Burette
d) Volumetric pipette
b) Bunsen burner
5. Which method can detect colorless substances in chromatography?
a) Heating the chromatogram
b) Using UV light or chemical locating agents
c) Adding more solvent
d) Measuring the pH of the spots
b) Using UV light or chemical locating agents
5. Which technique separates ethanol (boiling point: 78°C) from water (boiling point: 100°C)?
a) Simple distillation
b) Fractional distillation
c) Filtration
d) Decanting
b) Fractional distillation
5. What is the test for hydrogen gas?
a) Glowing splint relights
b) Limewater turns milky
c) Lighted splint produces a "squeaky pop"
d) Damp litmus paper turns blue
c) Lighted splint produces a "squeaky pop"