Percent Error
What item follows the answer in one of these problems?
Ex: -3 ___
Percent
The act of comparing unknown quantity to a standard unit is known as
measurement
How many significant figures does .038010 m have?
5
How many significant figures does .00010 s have?
2 Significant Figures
SI unit for length
meter (m)
Observed 4.0 g Expected 5.1 g
(A - B) / ( C ) x 100. =
Where does 4.0g go in this problem?
Position A
kg /(m x s^2 ) is an example of what type of unit ?
SI derived unit
How many significant figures does 1 ft/12 inches have ?
4.800 x 10 ^4 has how many Sig Figs in this notation?
4
SI unit for time
second (s)
Observed 3.61 mg Expected 3.62
(A-B) / (c) x 100
Where does 3.62 go in this problem?
A fraction that contains both the original unit and its equivalent value in a new unit. Ex: 12 inches = 1 ft
Conversion factor
How many Significant Figures do 170023 apples have?
None - Rule #1 it does not apply to counted numbers
Write 4800 mL in scientific notation with 3 Sig Figs
4.80 x 10^3 mL
SI unit for number of particles
mole (mol)
If you observed 6.2 mL and you were expected to get 6.8 mL will the percent be negative or positive?
Measurement that reflects a numerical evaluation of how close a measured value is to the expected or accepted value of then emission being measured is now as
Accuracy
250.00 L has how many significant figures?
5
When adding and subtracting, what is the rule for the number of significant figures in the answer?
Round to the least precise decimal place.
Ex: 11.53cm +11.53cm + 5.6cm + 5.6cm =
34.26 cm= FINAL 34.3cm
When Dividing or Multiplying measurements, what is the rule for the final answer?
Use the fewest number of Sig Figs in the problem for the answer.
Area (11.53cm) (5.6cm)
Area = 64.568 cm^2
Final = 65 cm^2
If you have a positive percent error of 7.0 % verses -1.2% error that your partner got, does that mean you got a more accurate result with a positive percent?
No, you want your percent error to be small in value whether its positive or negative. The positive or negative is only dealing with whether you got less than the expected or more than the expected value.
4.8 x 10^3
Scientific notation
2500 mL written in 2.50x10^2 mL has how many Sig Figs in the scientific notation?
3
How many Sig Figs does 6700000 have?
2
Write 5.07 x 10 ^ 3 in standard notation
5070