BTEC UNIT 2 APPLIED SCIENCE CHEMISTRY
EXAM 2025-2026 QUESTIONS AND ANSWERS
GRADED A+
Suggest why laboratory technicians must complete health and safety training
before they are allowed to work in the laboratory
to ensure that they are aware of the risk and hazards in laboratories and how to deal
with them.
Information that must be recorded for samples taken
date
name of person handling samples
location (where sample is from and where it is transported to)
Flame test colours
,Barium (Ba2+)= Pale Green
Copper= Green Blue
Lithium= Crimson Red
Sodium (Na+)= Yellow
Potassium (K+)= Lilac
Calcium (Ca2+)= Orange-red
Properties of a suitable internal standard
Internal standard is chemically related to the compounds that are being analysed
but it should not be naturally present in the sample.
Compounds which have the same functional groups.
Why are tubes containing blood samples enclosed in plastic watertight containers
Prevents degradation by water.
Two containers limits possibility of loss sample if one container is broken.
2 ways of reducing risks associated with hazards in labs
, Carry out risk assessment
Use PPE for protection
Train staff in necessary procedures
Comparing light and electron microscopes
Light Microscope
•Rely on light rays
•Typically magnify objects by 1000 to 2000 X
•Images seen in 2D
•Live specimen can be seen
Electron Microscope
•Electrons bombarded using high levels of energy
•Specimen is killed
•Colours cannot be detected
•Magnification roughly 2,000,000 X
How can the width of human hair be calculated using a graticule and a Light
Microscope
EXAM 2025-2026 QUESTIONS AND ANSWERS
GRADED A+
Suggest why laboratory technicians must complete health and safety training
before they are allowed to work in the laboratory
to ensure that they are aware of the risk and hazards in laboratories and how to deal
with them.
Information that must be recorded for samples taken
date
name of person handling samples
location (where sample is from and where it is transported to)
Flame test colours
,Barium (Ba2+)= Pale Green
Copper= Green Blue
Lithium= Crimson Red
Sodium (Na+)= Yellow
Potassium (K+)= Lilac
Calcium (Ca2+)= Orange-red
Properties of a suitable internal standard
Internal standard is chemically related to the compounds that are being analysed
but it should not be naturally present in the sample.
Compounds which have the same functional groups.
Why are tubes containing blood samples enclosed in plastic watertight containers
Prevents degradation by water.
Two containers limits possibility of loss sample if one container is broken.
2 ways of reducing risks associated with hazards in labs
, Carry out risk assessment
Use PPE for protection
Train staff in necessary procedures
Comparing light and electron microscopes
Light Microscope
•Rely on light rays
•Typically magnify objects by 1000 to 2000 X
•Images seen in 2D
•Live specimen can be seen
Electron Microscope
•Electrons bombarded using high levels of energy
•Specimen is killed
•Colours cannot be detected
•Magnification roughly 2,000,000 X
How can the width of human hair be calculated using a graticule and a Light
Microscope
