Measurements

• How many sig figs in 3400?

  • This is ambiguous. Could be 2, 3, or 4 sig figs, depending on measurement precision.
  • To resolve ambiguity, use scientific notation.
    • $3.4 \times 10^3$ has 2 sig figs
    • $3.40 \times 10^3$ has 3 sig figs
    • $3.400 \times 10^3$ has 4 sig figs

• 0.00016 has 2 sig figs.

  • 0s use to position the decimal point are not sig figs.
  • If written as $1.6 \times 10^{-4}$, it is clearer that there are 2 sig figs.