• Save
Chemistry - Significant Digits
Upcoming SlideShare
Loading in...5
×
 

Chemistry - Significant Digits

on

  • 1,155 views

 

Statistics

Views

Total Views
1,155
Views on SlideShare
1,155
Embed Views
0

Actions

Likes
0
Downloads
0
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

Chemistry - Significant Digits Chemistry - Significant Digits Presentation Transcript

  •  
  • Sample Question 1
    • Which is the most appropriate unit in which to measure the length of the McDevitt hallway?
    • a. millimeters b. grams
    • c. meters d. kilometers
  • Sample Question 2
    • There are 1,000 _____ in one liter?
    • a. milliliters b. centiliters
    • c. kiloliters d. SI liters
    View slide
  • Measurements View slide
  • Making Measurements
    • Always estimate the final digit.
  • Making Measurements
    • What’s the difference?
  • Accuracy vs. Precision
    • Precision = how close your measurements are to each other
    • Accuracy = how close your measurements are to the actual value
  • Sig. Figs.
  • In Math…
    • What’s the difference between:
    • 5.6,
    • 5.60, and
    • 5.600?
  • Significant Figures
    • All precisely-known digits, plus the final, estimated digit of a measurement.
  • Significant Figures
    • Include:
      • Any non-zero digit.
      • Zeroes that aren’t placeholders.
      • Zeroes between other significant digits.
  • Placeholder…?
    • To find out if the zero is a placeholder… REMOVE IT and see if the number is MATHEMATICALLY equal!
    • If it is not, the zero is a placeholder!
  • Which are significant?
    • 53 km
    • 2003 g
    • 30.000 mL
    • 919.1984 m
    • 204.6 kg
    • 10,000,000,000 L
    • 7080 mg
    • 77.01 mL
  • Which are significant?
    • 80 mL
    • 700,560 g
    • 45.05 cm
    • 62.000 L
    • 9,490.50 g
    • 80,000.1 mg
    • 78.10 kL
    • 69.000003003 L
  • Infinite Sig. Figs.
    • Exact, counted numbers
    • Example: “There are 28 students in the class.”
    • (Would not make sense to say that there are 28.00 students)
  • Working with Sig. Figs.
  • ROUNDING!
  • Adding and Subtracting
    • Find the quantity with the smallest number of decimal places .
    • Add/Subtract.
    • Keep the number of decimal places you found above.
  • Example
    • 17.85 g + 24.6105 g
    • 17.85 – 2 decimal places
    • 24.6105 – 4 decimal places
    • 17.85
    • + 24.6105
    • 42.4605
    • Should have TWO decimal places.
    • 42.46 g
  • Try These
    • 17.0 – 15.45 =
    • 65 + 21.0004 =
    • 107.22 – 45.23 =
    • 1.6
    • 86
    • 61.99
  • Multiplying and Dividing
    • Find the quantity with the smallest number of significant digits .
    • Multiply/Divide.
    • Keep the number of SIGNIFICANT DIGITS you found above.
  • Example
    • 7.800 m x 24.600 m
    • 7.800 – 4 significant digits
    • 24.600 – 5 significant digits
    • 7.800
    • x 24.600
    • 191.880000
    • Should have FOUR significant digits.
    • 191.9
  • Try These
    • 7.888 x 45.01 =
    • 4.010 x 30.1 =
    • 1984 / 9.19