Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by...
-
Upload
merilyn-mathews -
Category
Documents
-
view
229 -
download
3
description
Transcript of Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by...
![Page 1: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/1.jpg)
Unit 1 Notes
![Page 2: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/2.jpg)
The Metric SystemEasier to use because it is a decimal system.Every conversion is by some power of 10.• A metric unit has two parts.• A prefix and a base unit.• prefix tells you how many times to divide or multiply
by 10.• Example:
• centimeter
prefix Base unit
A centimeter= one hundredth of a meter
![Page 3: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/3.jpg)
The Fundamental SI Units (le Système International, SI)
Physical Quantity Name Abbreviation Mass kilogram kg Length meter m Volume Liter L Temperature Kelvin K Amount of Substance
mole mol
![Page 4: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/4.jpg)
Short cut to Converting
how far you have to move on this chart, tells you how far, and which direction to move the decimal place.
The box is the base unit, meters, Liters, grams, etc.
k h D d c m
![Page 5: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/5.jpg)
Short cut to Conversion
Change 5.6 m to millimeters
k h D d c m
starts at the base unit and move three to the right.move the decimal point three to the right
56 00
![Page 6: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/6.jpg)
MEASUREMENTAccuracy and Precision
![Page 7: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/7.jpg)
Types of Measurement
• Quantitative- use numbers to describe• Qualitative- use description without numbers• 4 feet• extra large• Hot• 100ºF
![Page 8: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/8.jpg)
Scientists prefer
Quantitative- easy check.Easy to agree upon, no personal bias.The measuring instrument limits how good the measurement is.
![Page 9: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/9.jpg)
Accuracy vs. Precision• Accuracy - how close a measurement is to the accepted
value
• Precision - how close a series of measurements are to each other
ACCURATE = CORRECTPRECISE = CONSISTENT
![Page 10: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/10.jpg)
Accuracy…
• To determine if data is accurate, ask yourself, “how close is this data point to the actual, accepted, or true value?
• In short, the closer your data is to the accepted or true value, the more accurate your data is.
![Page 11: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/11.jpg)
Precision…
•To determine if your data is precise, ask yourself, “How close are my data points to one another?”
• In short, the closer your
data points are to one another, the more precise your data points are.
![Page 12: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/12.jpg)
Sketch these in your journal…
AccuratePrecise
Not AccuratePrecise
Not AccurateNot Precise
AccurateNot Precise
![Page 13: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/13.jpg)
Differences
Accuracy can be true of an individual measurement or the average of several.
Precision requires several measurements before anything can be said about it.
![Page 14: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/14.jpg)
Percent Error
Indicates accuracy of a measurement
100literature
literaturealexperimenterror %
your value
accepted value
![Page 15: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/15.jpg)
Percent ErrorA student determines the density of a substance to be
1.40 g/mL. Find the % error if the accepted value of the density is 1.36 g/mL.
100g/mL 1.36
g/mL 1.36g/mL 1.40error %
% error = 2.9 %
![Page 16: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/16.jpg)
MeasurementsWhen we measure something, we can (and do)
always estimate between the smallest marks.
21 3 4 5
![Page 17: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/17.jpg)
MeasurementsThe better the marks, the better we can estimate.Scientist always understand that the last number
measured is actually an estimate.
21 3 4 5
![Page 18: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/18.jpg)
Significant FiguresIndicate precision of a measurement.Recording significant figures
Significant figures in a measurement include the known digits plus a final estimated digit
2.35 cm
![Page 19: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/19.jpg)
Significant FiguresCounting Sig Figs
Count all numbers EXCEPT:Leading zeros -- 0.0025Trailing zeros without
a decimal point -- 2,500
![Page 20: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/20.jpg)
Rules for Counting Significant Figures - Details
• Exact numbers have an infinite number of significant figures.
•1 inch = 2.54 cm, exactly
![Page 21: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/21.jpg)
4. 0.080
3. 5,280
2. 402
1. 23.50
Significant FiguresCounting Sig Fig Examples
4 sig figs
3 sig figs
3 sig figs
2 sig figs
![Page 22: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/22.jpg)
Rounding rules
• Look at the number behind the one you’re rounding.• If it is 0 to 4 don’t change it.• If it is 5 to 9 make it one bigger.• Round 45.462 to four sig figs.
![Page 23: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/23.jpg)
In science, we deal with some very LARGE numbers:
1 mole = 602,000,000,000,000,000,000,000 particles
In science, we deal with some very SMALL numbers:Mass of an electron =0.000000000000000000000000000000091 kg
Scientific Notation
![Page 24: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/24.jpg)
Imagine the difficulty of calculating the mass of 1 mole of electrons!
0.000000000000000000000000000000091 kg x 602000000000000000000000 ???????????????????????????????????
![Page 25: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/25.jpg)
Scientific Notation:A method of representing very large or very small numbers in the form:
M x 10n
M is a number between 1 and 10 n is an integer
![Page 26: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/26.jpg)
2 500 000 000
Step #1: Insert an understood decimal point
.
Step #2: Decide where the decimal must end up so that one number is to its left
Step #3: Count how many places you bounce the decimal point
123456789
Step #4: Re-write in the form M x 10n
![Page 27: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/27.jpg)
2.5 x 109
The exponent is the number of places we moved the decimal.
![Page 28: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/28.jpg)
0.0000579
Step #2: Decide where the decimal must end up so that one number is to its leftStep #3: Count how many places you bounce the decimal pointStep #4: Re-write in the form M x 10n
1 2 3 4 5
![Page 29: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/29.jpg)
5.79 x 10-5
The exponent is negative because the number we started with was less than 1.
![Page 30: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/30.jpg)
Scientific Notation
• Converting into Sci. Notation:• Move decimal until there’s 1 digit to its left. Places moved
= exponent.• Large # (>1) positive exponent
Small # (<1) negative exponent• Only include sig figs.
65,000 kg 6.5 × 104 kg
![Page 31: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/31.jpg)
Physical PropertiesA characteristic that can be observed or
measured without changing the identity of the substance
![Page 32: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/32.jpg)
States of Matter
![Page 33: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/33.jpg)
States of Matter• Solids
very low kinetic energy - particles vibrate but can’t move around
Retains size and shapeDefinite shape and volume
![Page 34: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/34.jpg)
States of Matter• Liquids
low kinetic energy - particles can move around but are still close together
Takes the shape of its container
definite volume
![Page 35: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/35.jpg)
States of Matter• Gases
high KE - particles can separate and move throughout container
Easily compressedNo definite shapeNo definite volume
![Page 36: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/36.jpg)
Some Properties of Solids, Liquids, and Gases
Property Solid Liquid Gas
Shape Has definite shape Takes the shape of Takes the shape the container of its container
Volume Has a definite volume Has a definite volume Fills the volume of the container
Arrangement of Fixed, very close Random, close Random, far apartParticles
Interactions between Very strong Strong Essentially noneparticles
![Page 37: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/37.jpg)
Physical ChangeA change in a substance that does not involve a change in the identity of the substance.
Examples:Phase Changes – boiling point, melting point, freezing point
A substance dissolving in another substance - solubility
![Page 38: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/38.jpg)
Chemical Properties• Relates to a substance’s
ability to undergo change that transforms it into a different substance
Ability to : combust, oxidize, neutralize, reactivity, etc.
![Page 39: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/39.jpg)
Chemical ChangeA change in which one or more substances are converted into different substances.
Evidence of Chemical Change: Heat and light Change in color Production of gas Precipitation of a solid
![Page 40: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/40.jpg)
Temperature is Average Kinetic Energy
Fast Slow“HOT” “COLD”
![Page 41: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/41.jpg)
Celcius & Kelvin Temperature Scales
![Page 42: Unit 1 Notes The Metric System Easier to use because it is a decimal system. Every conversion is by some power of 10. A metric unit has two parts. A.](https://reader035.fdocuments.net/reader035/viewer/2022062523/5a4d1af37f8b9ab05997f4e7/html5/thumbnails/42.jpg)
Measuring Temperature
• Kelvin starts at absolute zero (-273 º C)• degrees are the same size• C = K -273• K = C + 273• Kelvin is always bigger.• Kelvin can never be negative.
273 K