General Rules for Chemistry Diagrams (Copy)

🧪 Expanded Section: General Rules for Chemistry Diagrams in Alternate to Practical (ATP)

✏️ 1. Use a Sharp HB Pencil Only

• No pens or colors allowed unless a colored flame or specific instruction is given.
• Pencil allows for clear, clean lines and erasability — crucial for marks.
• HB is preferred over softer (e.g., 2B) or harder (e.g., H) pencils due to balanced darkness and neatness.

📏 2. Draw Clean, Continuous Lines

• No sketching: Diagrams must not look rough or uncertain.
• Avoid double lines unless explicitly required (e.g., for the outer wall of a condenser).
• Keep line weight consistent — too thick or too faint lines may lose marks.

📐 3. Use a Ruler Wherever Possible

• All apparatus (test tubes, flasks, condensers) should be drawn with neatly ruled straight lines for structural parts (e.g., burette, pipette, clamps).
• Label lines must be horizontal and straight.
• Ensure vertical parts (e.g. burette, stand) are aligned and not slanted.

⚖️ 4. Keep the Drawing Proportional

• Make sure the relative sizes of equipment are realistic:
  • Test tubes should be thinner and shorter than boiling tubes.
  • Burettes should be long and narrow.
  • Conical flasks should have a wide base and narrow neck.
• Avoid comically large or squeezed components — they reduce clarity and look unprofessional.

📐 5. Fill at Least Half the Space Provided

• Small, cramped drawings get penalized even if technically correct.
• Use the full width or height of the space (depending on orientation).
• A large diagram shows attention to detail and is easier to label clearly.

🏷️ 6. Label Clearly with Horizontal Lines

• All labels must be:
  • Written in pencil
  • Horizontally aligned
  • Not crossing other lines or arrows
  • Without arrowheads, just straight lines touching the object being labeled
• Use standard chemical names:
  • “Dilute hydrochloric acid” not just “acid”
  • “Hydrogen gas” not just “gas”

🚫 7. No Shading or Coloring

• Even for flames or liquids — use line patterns or annotations instead:
  • Label as “blue flame” or “ethanol solution” instead of shading
• Exception: chromatography may ask for colors — draw dots and label colors clearly (still with pencil).

🔍 8. Ensure All Essential Parts Are Present

• Don’t draw extra equipment that isn’t asked — stick to what’s required.
• If asked for a labeled diagram of “gas collection over water,” don’t draw an entire titration setup.
• Missing even one key component (like a delivery tube, stopper, thermometer bulb, or funnel) can cost you the mark.

✅ 9. Use Neat Handwriting for Labels

• Even if your drawing is excellent, untidy or unclear handwriting can make a label unreadable.
• Write slightly larger than your usual size for labels.
• Avoid cursive or artistic fonts. Use block capital letters where needed.

🔄 10. Check Before Moving On

After drawing:

• Go through a mental checklist: Are all items in place? Are labels straight and accurate? Did I forget water direction in the condenser?
• Spend 20 seconds reviewing before finishing — it can save marks.

🧠 Pro Tip:

Think like the examiner. If your diagram was given to a complete stranger, would they understand what’s happening without the question paper? If not, it’s not exam-ready.