Study guide: Science Laboratory Vademecum

📋 Course Outline

1. Laboratory Safety and Hazard Labels
2. Fire Response and First Aid
3. Scientific Investigation Method
4. Laboratory Equipment and Glassware
5. Balances Microscopes and Pipettes
6. Heating Filtration and Fume Hoods
7. Measurement and Scientific Notation
8. Graphs Forces and Physics Formulas
9. Chemical Risk Assessment and Waste
10. Scientific Sources and Core Terminology

📖 1. Laboratory Safety and Hazard Labels

★ Must-know

📌 H-sentences indicate the hazards associated with a chemical substance, whereas P-sentences indicate the safety measures required when working with it.

• The hazard symbols cover:
  • explosive
  • flammable
  • oxidizing
  • pressurized
  • harmful
  • environmentally hazardous
  • long-term health hazardous
  • corrosive
  • toxic

Further detail

📌 Concentrated products are more dangerous than diluted substances.

💡 Memory Hook

H-zinnen describe hazards, whereas P-zinnen prescribe precautions.

📖 2. Fire Response and First Aid

🔑 Key Concepts & Definitions

• Fire: Fire requires fuel, an ignition temperature, and oxygen.

★ Must-know

• A fire can be extinguished by: removing the fuel, removing or smothering the oxygen, cooling the fire below its ignition temperature

📌 If clothing catches fire, the person must not run away but must roll on the floor and cover the clothing with a blanket or wet cloths.

📌 Skin exposed to splashes must be rinsed abundantly with water for a minimum of 10 minutes, using the emergency shower when necessary.

Further detail

• The emergency numbers are 112 for medical emergencies and the fire brigade, 101 for the police, and 070 245 245 for the poison centre.

💡 Memory Hook

Remove fuel, oxygen, or heat → combustion stops.

📖 3. Scientific Investigation Method

🔑 Key Concepts & Definitions

• Research question: a central, clearly delimited question that the investigation aims to answer
• Hypothesis: a predictive, testable answer or explanation for a research question

📝 Essential Points

• 🔄 A scientific investigation proceeds through:
  1. the research question
  2. the hypothesis
  3. the materials
  4. the procedure
  5. the observations
  6. the conclusion
  7. the reflection

📌 Good observations are objective, specific, measurable when possible, and reproducible by others.

💡 Memory Hook

Question → hypothesis → plan → observation → conclusion → reflection

📖 4. Laboratory Equipment and Glassware

★ Must-know

• Volumetric glassware is designed to measure a specific liquid volume accurately, whereas non-volumetric glassware cannot be used for accurate volume measurement.

• Soda-lime glass is not resistant to heating, whereas borosilicate glass such as Jena, Duran, or Pyrex is suitable for heating.

• For a concave meniscus, the lower surface is read at eye level, while for a convex meniscus, the upper surface is read at eye level.

Further detail

• Examples of volumetric glassware are:
  • volumetric pipettes
  • graduated pipettes
  • measuring cylinders
  • volumetric flasks

💡 Memory Hook

Volumetric glassware measures accurately, whereas non-volumetric glassware does not.

📖 5. Balances Microscopes and Pipettes

★ Must-know

• 🔄 To determine mass:

  1. place the weighing vessel on the balance
  2. tare the balance to zero
  3. add the solid substance with a spatula

• 🔄 To use a microscope:

  1. select the lowest magnification
  2. illuminate the specimen
  3. secure the specimen
  4. focus with coarse adjustment
  5. focus with fine adjustment
  6. regulate the diaphragm

• 🔄 To prepare a slide:

  1. place one drop of water on a slide
  2. add the specimen
  3. optionally add stain
  4. place the coverslip
  5. remove excess liquid

Further detail

• 🔄 A pipette is rinsed by:
  1. drawing up water
  2. rotating the horizontal pipette
  3. draining the water into a waste container

💡 Memory Hook

Prepare → measure or observe → clean → store

📖 6. Heating Filtration and Fume Hoods

🔑 Key Concepts & Definitions

• Fume hood: protects the user from harmful vapours, gases, and splashes by extracting contaminated air

📝 Essential Points

📌 Inside a fume hood, the sash should be as low as possible, the head must remain outside, and work must be performed at least 15 cm from the front edge.

• Filtration separates a mixture when the residue remains on the filter paper and the filtrate passes through it.

📌 When heating a test tube, use heat-resistant borosilicate glass, hold it at a 45° angle with its opening directed away from people, and move it continuously through the flame.

📖 7. Measurement and Scientific Notation

🔑 Key Concepts & Definitions

• SI units: internationally agreed units used to express the seven base quantities and derived quantities consistently

★ Must-know

📌 Accuracy describes how close a measured value is to the true value, whereas precision describes how close repeated measurements are to one another.

📌 For addition and subtraction, round the result to the smallest number of decimal places, whereas for multiplication and division, round it to the smallest number of significant figures.

Further detail

📌 The last digit of a measurement is always an estimated digit and indicates the reading precision of the instrument.

📐 Formula — The volume conversion uses $1\,\mathrm{L}=1\,\mathrm{dm^3}$ and the SI unit of volume is $\mathrm{m^3}$.

💡 Memory Hook

Accuracy concerns closeness to the true value, whereas precision concerns agreement between repeated values.

📖 8. Graphs Forces and Physics Formulas

🔑 Key Concepts & Definitions

• Force: an interaction that can change an object's speed, direction of motion, or shape

★ Must-know

• A force vector is represented by an arrow characterized by its point of application, direction, sense, and magnitude.

Further detail

📐 Formula — The kinetic energy is $E_{\mathrm{kin}}=\frac{1}{2}mv^2$.

📐 Formula — The gravitational potential energy is $E_{\mathrm{pot,grav}}=mgh$.

📐 Formula — Mechanical work is $W=F\Delta x\cos\alpha$.

📖 9. Chemical Risk Assessment and Waste

🔑 Key Concepts & Definitions

• Water hazard class: indicates how polluting a substance is for water

★ Must-know

• 🔄 A chemical risk analysis requires:
  1. identifying the substance and concentration
  2. selecting safety measures
  3. providing a justification when required
  4. obtaining teacher approval
  5. producing the analysis as a PDF

📌 A laboratory coat is always required; safety glasses are required when working with corrosive substances or a Bunsen burner, while gloves are used only when explicitly required by the dBGS.

• Chemically contaminated solid material, including tissues, gloves, and contaminated filter paper, must not be placed in ordinary waste and belongs to category 12.

Further detail

• The waste categories include:
  • inorganic acids in category 1
  • organic acids in category 2
  • bases in category 3
  • halogen-free organic solvents in category 4
  • toxic chemicals in category 6
  • oxidizing substances in category 9
  • contaminated glass in category 10

💡 Memory Hook

Identify → assess → protect → approve → dispose

📖 10. Scientific Sources and Core Terminology

🔑 Key Concepts & Definitions

• Reliable scientific source: written by experts, based on evidence, checked by other experts through peer review, and accompanied by clear references
• Hypothesis: a provisional, testable explanation or prediction used as a starting point for further research
• Density: the mass of a substance per unit of volume

📝 Essential Points

• A source should be assessed by checking:
  • the author's expertise
  • the publication venue
  • the references
  • the currency
  • the objective factual tone

📌 Correlation is a statistical association between variables, whereas causality means that a change in one variable directly causes a change in another.

💡 Memory Hook

Correlation shows association, whereas causality shows a direct cause-and-effect relationship.

📊 Synthesis Tables

Measurement Concepts