Material Required
1. What is required to ensure safety when handling chemicals?
- a) Water bottles
- b) Rubber band
- c) *Gloves and safety goggles*
- d) Dish soap
2. Which item is not listed in the required materials?
- a) Water
- b) *Bunsen burner*
- c) Dish soap
- d) Rubber band
Procedure for Preparing a Wash Bottle.
3. What should you verify before using the wash bottle?
- a) If it is full
- b) *If it is clean and dry*
- c) If it has a label
- d) If it is empty
4. What should be inserted into the rubber stopper?
- a) Long piece of tubing
- b) *Short piece of glass or plastic tubing*
- c) Funnel
- d) Beaker
5. How should you secure the wash bottle to prevent tipping?
- a) Place on a flat surface
- b) *Attach to a lab stand or ring stand*
- c) Hold by hand
- d) None of the above
6. What is used to create a tight seal around the neck of the wash bottle?
- a) Funnel
- b) *Grommet or rubber washer*
- c) Clamp
- d) Glass tube
7. What should you use to pour the desired liquid into the wash bottle?
- a) Beaker
- b) *Funnel*
- c) Dropper
- d) Pipette
8. How do you dispense the liquid from the wash bottle?
- a) By shaking it
- b) *By gently squeezing it*
- c) By tilting it
- d) By pouring it
9. What should you do after testing the wash bottle?
- a) Discard it
- b) *Label it with contents and safety information*
- c) Clean it again
- d) Store it without labeling
Crystallization of Naphthalene
10. What should you wear before starting the crystallization process?
- a) *Gloves and goggles*
- b) Lab coat
- c) Safety shoes
- d) Hairnet
11. What is added to the impure naphthalene to dissolve impurities?
- a) *Non-polar solvent (e.g., petroleum ether)*
- b) Water
- c) Acid
- d) Alcohol
12. How do you filter the hot solution?
- a) Use a strainer
- b) *Set up a filtration apparatus with filter paper or a Büchner funnel and filter flask*
- c) Use a funnel and cloth
- d) Pour it into another beaker
13. Where should the clear naphthalene solution be transferred for crystallization?
- a) *To a dish*
- b) To a flask
- c) To a jar
- d) To a beaker
14. How are the naphthalene crystals collected?
- a) *By draining off any remaining liquid and air-drying*
- b) By boiling
- c) By pouring out the solution
- d) By freezing
Sublimation of Naphthalene
15. How much mixture should be placed on the China dish?
- a) 1g
- b) 2g
- c) *5g*
- d) 10g
16. What is used to prevent vapors from escaping during sublimation?
- a) *Inverted funnel with cotton plug*
- b) Lid
- c) Another dish
- d) Plastic wrap
17. How long should the sand bath be heated?
- a) 2-3 minutes
- b) *5-10 minutes*
- c) 15-20 minutes
- d) 30 minutes
18. Where are the pure naphthalene crystals observed?
- a) On the sand bath
- b) *On the filter paper*
- c) In the China dish
- d) In the beaker
Melting Point Determination
19. What is used to crush the naphthalene into a fine powder?
- a) *Tile*
- b) Mortar and pestle
- c) Beaker
- d) Spoon
20. At what point should the temperature be noted during melting?
- a) When the water starts boiling
- b) When the water cools down
- c) *When the naphthalene starts and finishes melting*
- d) When the thermometer breaks
Boiling Point Determination
21. What is attached to the thermometer using a thread?
- a) *Fusion tube*
- b) Capillary tube
- c) Beaker
- d) Stand
22. What indicates the boiling point of the compound?
- a) Change in color
- b) *Continuous stream of bubbles*
- c) Change in smell
- d) Melting of the substance
Preparing 0.1M NaOH Solution
23. What is the molar mass of NaOH?
- a) 30 g/mol
- b) *40 g/mol*
- c) 50 g/mol
- d) 60 g/mol
24. How much NaOH is required to make 0.1M solution in 100cm3 of water?
- a) 0.2 g
- b) 0.3 g
- c) *0.4 g*
- d) 0.5 g
Standardization of NaOH Solution
25. What indicator is used in the standardization of NaOH with oxalic acid?
- a) Methyl orange
- b) **Phenolphthalein**
- c) Bromothymol blue
- d) Litmus
26. What is the endpoint color change in the titration of oxalic acid with NaOH?
- a) *Colorless to light pink*
- b) Blue to red
- c) Yellow to green
- d) Red to blue
Normality Determination of H2SO4
27. What is the standard solution used in the titration of H2SO4?
- a) *0.1M NaOH*
- b) 0.1M HCl
- c) 0.1M KOH
- d) 0.1M NH4OH
28. What is the endpoint color change in the titration of NaOH with H2SO4?
- a) Red to yellow
- b) *Light pink to colorless*
- c) Blue to green
- d) Purple to orange
Acetic Acid in Vinegar
29. What is the standard solution used in determining the amount of acetic acid in vinegar?
- a) *0.05M NaOH*
- b) 0.1M HCl
- c) 0.1M NH4OH
- d) 0.05M KOH
30. What is the end-point indicator used in the titration of acetic acid in vinegar?
- a) *Phenolphthalein*
- b) Methyl orange
- c) Bromothymol blue
- d) Litmus
Standardizing KMnO4 Solution
31. What is the principle used in standardizing KMnO4 solution?
- a) *Oxidation-Reduction Titration*
- b) Precipitation Titration
- c) Complexometric Titration
- d) Acid-Base Titration
32. What is the endpoint indicator for KMnO4 titration?
- a) *KMnO4 itself*
- b) Phenolphthalein
- c) Methyl orange
- d) Bromothymol blue
General Lab Procedures
33. What should be done if NaOH solution spills?
- a) Wipe it with a cloth
- b) Let it evaporate
- c) *Neutralize with acid and clean up immediately*
- d) Cover it with sand
34. How should NaOH be added to water?
- a) All at once
- b) *Slowly with constant stirring*
- c) Quickly without stirring
- d) In small chunks
35. How should the solution be labeled?
- a) With the name and date
- b) *With concentration and date*
- c) With volume and date
- d) With the name and concentration
Additional Questions
36. What is used to secure the wash bottle to prevent tipping?
- a) *Lab stand or ring stand*
- b) Beaker
- c) Flask
- d) Clamp
37. How should the NaOH solution be mixed thoroughly?
- a) Shake the beaker
- b) *Turn the measuring flask upside down*
- c) Stir with a glass rod
- d) Mix with a spoon
38. What is the mole ratio of H2SO4 to NaOH in their
titration reaction?
- a) 1:1
- b) *1:2*
- c) 2:1
- d) 2:2
39. What happens to the naphthalene when heat is applied during sublimation?
- a) Melts
- b) *Vaporizes and then condenses*
- c) Dissolves
- d) Burns
40. What is the approximate normality of H2SO4 if 25cm3 of 0.1M NaOH is required for titration?
- a) 0.1N
- b) *0.05N*
- c) 0.2N
- d) 0.025N
41. How do you ensure safety during titration procedures?
- a) Use gloves only
- b) Use goggles only
- c) *Use gloves and goggles*
- d) Use a lab coat
42. What is the color of phenolphthalein in a basic solution?
- a) Colorless
- b) *Pink*
- c) Yellow
- d) Blue
43. How should pure naphthalene crystals be stored?
- a) *In a dry container*
- b) In a wet container
- c) In an open dish
- d) In a plastic bag
44. What is the first step in the crystallization of naphthalene?
- a) *Wear gloves and goggles*
- b) Heat the solution
- c) Filter the solution
- d) Collect the crystals
45. How should the remaining liquid be handled after collecting naphthalene crystals?
- a) *Drained off and discarded safely*
- b) Mixed with other chemicals
- c) Left in the dish
- d) Used for another experiment
46. What is the concentration of a 0.1M solution of NaOH?
- a) *0.1 moles per liter*
- b) 0.1 grams per liter
- c) 1 mole per liter
- d) 10 moles per liter
47. Why is it important to label the wash bottle?
- a) To show ownership
- b) *To indicate contents and safety information*
- c) To prevent theft
- d) For aesthetic purposes
48. What should be done with the wash bottle after use?
- a) Throw it away
- b) *Rinse and store properly*
- c) Leave it on the bench
- d) Use it for another solution
49. What is the endpoint color of phenolphthalein in an acid-base titration?
- a) Blue
- b) Green
- c) *Light pink*
- d) Yellow
50. What should be done if the naphthalene does not dissolve completely?
- a) *Add more solvent*
- b) Heat less
- c) Cool down
- d) Shake vigorously
