Answer
🧪 Significant Figures in Multiplication and Division
🎯 Core Concept
When multiplying or dividing measured values:
📌 The final answer must have the same number of significant figures as the measurement with the fewest significant figures.
📌 The final answer must have the same number of significant figures as the measurement with the fewest significant figures.
🔍 Example 1: 340 g ÷ 63.761 mL
340 g → 2 sig figs
63.761 mL → 5 sig figs
340 ÷ 63.761 = 5.332…
✔️ Final Answer: 5.3 g/mL (2 sig figs)
🔍 Example 2: 355.6 g ÷ 0.65 mL
355.6 g → 4 sig figs
0.65 mL → 2 sig figs
355.6 ÷ 0.65 = 547.0769…
✔️ Final Answer: 550 g/mL (2 sig figs)
🔍 Example 3: 7.8084 mol/L × 3.825 L
7.8084 → 5 sig figs
3.825 → 4 sig figs
7.8084 × 3.825 = 29.86913
✔️ Final Answer: 29.86 mol (4 sig figs)
✅ Summary Rule Table
| Operation | Rule |
|---|---|
| Multiplication | Use the fewest significant figures among the inputs |
| Division | Use the fewest significant figures among the inputs |
| Rounding | Round only at the end, not during intermediate steps |