Unformatted text preview: c.c. = 1cm3 = 1ml
Significant Figures
All nonzero numbers are significant
1.Any zero trapped between nonzero numbers is significant (123.9087 = 7 sf)
2.Any zero to the left of the first nonzero number is NOT significant (0.01729 = 4sf)
4. Zeroes on the right of the last nonzero digit must be considered carefully:
1.e.g., consider 120 is this two or three sig figs?
Decimal Places
How many numbers do you have after the decimal point?
Here we don’t care if the number is nonzero or not.
How many decimal places for each of these?
0.0123 and 0.1452
MAKING MEASUREMENTS
All measuring devices have some sort of scale. We can be certain of a measurement’s value based on the
closest, smallest marks, but what if the actual value is somewhere in between?
We ESTIMATE. This then is our measurement. The last digit is the doubtful one, we guessed it. Example:
where is the end of the line? Rounding Rules :
ADDITION OR SUBTRACTION:
You can only have as many DECIMAL PLACES as there are in t...
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 Spring '08
 walker
 Chemistry

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