Unit 2: Experimental Techniques in Chemistry

41. In a chemical experiment, which tool is used to accurately measure a small volume of liquid?

a) Beaker
b) Graduated cylinder
c) Pipette
d) Erlenmeyer flask
Answer: c) Pipette

42. A common use of a burette in a titration experiment is to:

a) Measure the temperature
b) Add reactants gradually and accurately
c) Mix solutions
d) Separate liquids
Answer: b) Add reactants gradually and accurately

43. The primary purpose of using a hot plate in a laboratory is to:

a) Measure temperature
b) Stir solutions
c) Heat substances
d) Filter liquids
Answer: c) Heat substances

44. The technique of separating a mixture into its individual components based on their different affinities to a stationary phase and a mobile phase is known as:

a) Filtration
b) Chromatography
c) Distillation
d) Centrifugation
Answer: b) Chromatography

45. The device used to measure the concentration of a solution by analyzing its absorbance of light is a:

a) Spectrophotometer
b) Centrifuge
c) Refractometer
d) pH meter
Answer: a) Spectrophotometer

46. Which of the following is used to evaporate solvents from a solution quickly?

a) Water bath
b) Hot plate
c) Vacuum desiccator
d) Centrifuge
Answer: b) Hot plate

47. The process of heating a solid to produce a vapor and then cooling it to obtain the solid again is called:

a) Sublimation
b) Crystallization
c) Filtration
d) Distillation
Answer: a) Sublimation

48. In which technique is a solution poured through a funnel lined with filter paper to separate solids from liquids?

a) Filtration
b) Distillation
c) Crystallization
d) Chromatography
Answer: a) Filtration

49. The primary use of a centrifuge in a laboratory is to:

a) Separate components based on density
b) Measure temperature
c) Measure volume
d) Mix solutions
Answer: a) Separate components based on density

50. The purpose of using a reflux condenser in a chemical reaction is to:

a) Increase the temperature of the reaction
b) Prevent loss of vapor
c) Separate mixtures
d) Measure the pH of the solution
Answer: b) Prevent loss of vapor