Learning Goal – to understand the importance of significant figures

Questions over the reading Demonstrations with physical and

chemical changes? Notes / practice with significant figures Homework

Questions over Sec 3.1 and 3.21. What is the difference between a qualitative

and quantitative measurement?a. Give an example of each.

2. Record 6,510,000 in scientific notation

3. Write out 1.54 x 10-3.

4. Which set of measurements are the most precise?

a. 3g, 2.5g, 2gb. 3.0g, 2.5g, 2.0gc. 1g, 2g, 3gd. 1g, 1.5g, 2.5g

Why are significant figures important? What is the volume in the following

containers?

Always estimate the last digit

What is the measurement of the metal bar based on the left and right rulers?

Sig Fig “Rules” Imagine a map of the US:

If the decimal is Absent, count from the Atlantic side

If the decimal is Present, count from the Pacific side

Always start counting with the first non-zero digit

Pacific Side(decimal is present)

Atlantic Side(decimal is absent)

Let’s Practice!

Determine the number of sig figs in the following:

100100.40.00.00812.0755000

1 sig fig3 sig figs3 sig figs2 sig figs4 sig figs1 sig figs

Take out your planner and record your homework: Due Friday

Finish Sig Fig wkst and check answers online

Read and take notes over Sec 3.3, 3.4 & 3.5

Due Monday Sig Fig quiz on Moodle by Monday!