Significant Figures

• What are the 5 rules when evaluating Significant Figures?

  Rule 2. Captive Zeros

  Rule 4. Trailing Zeros

  Rule 1. Nonzero Digits

  Rule 3. Leading Zeros

  Rule 5. Final Zeros
• Captive Zeros - Zeros between nonzero

  digits are significant.
• Final zeros - Zeros at the end of a number

  that lies to the left of an understood decimal point may or may not be significant.
• What is the rule of significant figures shown here?(Example: 0.3400 ml, 22.000 g, 3.000000 ml)

  Trailing Zeros
• What is the rule of significant figures shown here?(Example: 0.1459 ml, 0.009 g, 0.00373 ml)

  Leading Zeros
• When measurements are added or subtracted, the answer cannot have more decimal places than those in the least accurate measurement.
• When measurements are multiplied or divided, it is the significant figures, not the number of decimal places, in each measurement that are counted. The answer cannot contain more significant figures than those in the least accurate measurement.
• Density a

  3.250g = 0.346851654 g/mL

  9.37ml

  Since 3.250 has four significant figures, and 9.37 has only three significant figures, the calculated density should have three significant figures. Thus, 0.346851654 g/mL should be rounded to three significant figures, resulting in a calculated density that is 0.347 g/mL.