Sig Fig Rules

• Numbers 1-9 are significant


  ex: 89564 (5 sig figs)

  
  

  rule #1
• Zeros between numbers 1-9 are significant


  ex: 8008 (4 sig figs)

  
  

  rule #2
• Zeros to the left of numbers 1-9 (to right of decimal point) are place holders *NOT significant


  ex: 0.0000457 (3 sig figs)

  
  

  rule #3
• (for numbers >1) Zeros to right of decimal point are significant


  ex: 5.0 (2 sig figs)

  8.030 (4 sig figs)

  
  

  rule #4
• (for numbers <1) Zeros between and at end of numbers 1-9 are significant


  ex: 0.0000560 (3 sig figs)

  
  

  rule #4
• Scientific notation to avoid uncertainty w/ trailing zeros


  ex: instead of 5600

  5.6 x 10^3 (2 sig figs)

  5.60 x 10^3 (3 sig figs)

  
  

  rule #5
• answer = no more digits to right of decimal than # with least number of digits to right of decimal

  ex: 5.32 + 12.4 + 6.425 + 19.27 = 43.415 but it would be 43.4 because of 12.4 (only goes to the tenths place)

  addition/subtraction
• answer = no more sig figs than # with the lease # of sig figs

  ex: 7.55 x 0.34 = 2.567 but this is rounded to 2.6 because 0.34 has only 2 sig figs

  multiplication/division