Transcript SI Base Units, Metric System, Factor Label Method Conversions

1. Define SI Base Units for Mass, Length, Time,
Temperature, Amount of a substance, Electric Current,
and Luminous Intensity
2. Explain how adding a prefix changes a unit.
3. Perform Density and Temperature Calculations.
4. Perform Unit Conversions using Factor Label Method.
5. Convert data from standard form to scientific notation
and from scientific notation to standard form.
6. Use various measuring devices to determine precision
and accuracy.
1. Quantitative Data
12. Candela
2. Qualitative Data
13. Density
3. Hypothesis
14. Volume
4. Base Unit
15. Absolute Zero
5. Kilogram
16. Scientific Notation
6. Meter
17. Precision
7. Liter
18. Accuracy
8. Second
19. Metric Ruler
9. Kelvin
20. Graduated Cylinder
10. Mole
21. Meniscus
11. Ampere
22. Triple Beam Balance
Scientific Law – A rule or principle describing a physical
relationship or event that is observed and experimented,
and NEVER changes.
Scientific Theory – A set of widely accepted explanations of
observations and phenomena, CAN change if there is
consistent evidence.
Scientific Hypothesis – A tentative explanation for an
observation or phenomenon, used to make predictions.
Qualitative Data: Observations made by scientists that
describes the information using the five senses – sight, smell,
taste, sound, touch.
Examples: Mr. A is wearing a green shirt, Mr. A has a loud
voice, A Lemon has a sour taste, Tape feels sticky, etc.
Quantitative Data: Observations made by scientists that
describes the numerical value of information.
Examples: Mr. A is 6’1” tall, Mr. A has 10 fingers and toes,
The classroom is 78 degrees Fahrenheit, You got 9 out 10
correct on the Lab Safety Test, etc.
When you do something with an observation, like draw a
conclusion, offer an explanation or decide that a chemical
reaction occurred, then you are making an inference.
An observation is the awareness of some condition; inference
is the result of a mental process which attempts to explain or
catalog or speculate about that observation.
The Significance of a measurement is determined by the precision and
accuracy of the device being used.
Accuracy – Refers to how close a measured value is to an accepted
value. Correctness
Precision – Refers to how close a series of measurements are to one
another. Consistency
From the following data table determine the precision and accuracy for
students A, B, and C. The following are test results based on 100%.
Student A
Student B
Student C
Trial 1
72%
93%
95%
Trial 2
70%
66%
97%
Trial 3
71%
77%
98%
Average
71%
78.66%
96.66%
Precise
Neither
Both
Base Unit: A defined unit in a system of measurement
based on an object or event in the physical world.
Quantity
Mass
Base Unit
Kilogram (kg)
Length
Meter (m)
Time
Second (s)
Temperature
Kelvin (K)
Amount of a substance
Mole (mol)
Electric Current
Ampere (A)
Luminous Intensity
Candela (cd)
Scientific Notation
Example
1 000 000 000
109
Gigameter (Gm)
M
1 000 000
106
Megagram (Mg)
Kilo
k
1 000
103
Kilometer (km)
Hecto
h
100
102
Hectoliter (hL)
Deca
da
10
101
Decagram (dag)
Deci
d
1/10
10-1
Deciliter (dL)
Centi
c
1/100
10-2
Centimeter (cm)
Milli
m
1/1000
10-3
Milligram (mg)
Micro
µ
1/1 000 000
10-6
Microgram (µg)
Nano
n
1/1 000 000 000
10-9
Nanometer (nm)
Prefix
Symbol Factor
Giga
G
Mega
1 Dozen eggs = 12 eggs
12 inches = 1 foot
60 seconds = 1 minute
16 ounces = 1 pound
Factor Label Method: A way to convert a ratio of equivalent values to
express the same quantity in different units.
Examples:
24 inches = ____?____ feet
24 inches
1 feet
12 inches
Given Units
Units to Get to
Units to Cancel
= 2 feet
Equivalent
Ratio
180 seconds = _____?______ minutes
180 seconds
1 minute
= 3 minutes
60 seconds
4800 grams = _____?______ kilograms
4800 grams
1 kilogram
= 4.8 kilograms
1000 grams
12 meters = _____?______ decimeters
12 meters
10 decimeters
1 meter
= 120 decimeters
7200 seconds = _____?______ hours
7200 seconds
1 minute
60 seconds
1 hour
60 minutes
= 2 hours
5500 centimeters = _____?______ kilometers
5500 centimeters
1 meter
100 centimeters
1 kilometers
= .055 kilometers
1000 meters
125.5 micrograms = _____?______ kilograms
125.5 micrograms
1 gram
1 000 000 micrograms
1 kilograms
1000 grams
= .0000001255 kg
Volume: the amount of space occupied by an object. Can
measured in Liters, milliliters, ounces, quarts, pints, gallons,
and cubic centimeters (cm3).
Volume = length x width x height
Density: the mass per unit volume of a given material.
Equation: Density = Mass / Volume
Examples – Water has a density of 1.0 g/mL
Ice has a density of 0.92 g/mL
Aluminum has density of 2.7 g/mL
What has a greater density oil or water?
What has a greater density, a brick or a pillow?
Hot and Cold are qualitative descriptions of temperature. Using the
three different temperature scales describes a quantitative observation.
The three temperature scales include; Celsius, Fahrenheit, and Kelvin
1. °C = (°F – 32) / 1.8
Known Values for Water
2. °F = 1.8(°C) + 32
Freezing Point of Water = 0 °C, 32 °F, 273K
3. K = °C + 273
Boiling Point of Water = 100 °C, 212 °F, 373K
Absolute Zero – The temperature at which a substance would have zero
kinetic energy, particles are not moving at all.
(0 K, -273 °C, - 459.4 °F)
Do the following Temperature Conversions:
111.2 °F
40 °C
a. 44 °C = _______
b. 104 °F = _______
398
c. 125 °C = ______K
Scientific Notation: expresses numbers as a multiple of two factors; a
number between 1 and 10 (M); and 10 raised to a power, or exponent (n)
General Formula: M x 10n
M = a number between 1-10 but cannot be 10 (1 - 9.999)
n = the number of decimal places moved
Examples: 1,000 = 1.0 x 103
150,000 = 1.5 x 105
498 = 4.98 x 102
8,542,327 = 8.542327 x 106
0.005 = 5.0 x 10-3
0.04005 = 4.005 x 10-2
0.0000652 = 6.52 x 10-5
100 = 1
so 4.1 x 100 = 4.1