ch 1. measurements have two parts: a ___ and a ___
number, scale
ch 1. the scale is called a ___
unit
ch 1. what are the two major systems of measurements?
English system and metric system
ch 1. what is the modified metric system called?
the international system of units/system international (SI unit)
ch 1. SI unit of mass
kilogram (kg)
ch 1. SI unit of length
meter (m)
ch 1. SI unit of time
second (s)
ch 1. SI unit of temperature
Kelvin (K)
ch 1. SI unit of electric current
ampere, A
ch 1. SI unit of amount of substance
mole (mol)
ch 1. SI unit of luminous intensity
candela (cd)
ch 1. derived units
Units we get from the base units
ch 1. derived unit of area
square meter (m^2)
ch 1. derived unit of volume
cubic meter (m^3)
ch 1. derived unit of force
Newton (N)
ch 1. derived unit of pressure
Pascal (Pa)
ch 1. derived unit of energy
Joule (J)
ch 1. derived unit of voltage
Volt (V)
ch 1. derived unit of frequency
Hertz (Hz)
ch 1. derived unit of electric charge
Coulomb (C)
ch 1. mega- (M)
10^6 (1,000,000)
ch 1. Kilo- (K)
10^3 (1,000)
ch 1. deci- (d)
10^-1 (0.1)
ch 1. centi- (c)
10^-2 (0.01)
ch 1. milli- (m)
10^-3 (0.001)
ch 1. micro- (μ)
10^-6 (0.000001)
ch 1. nano- (n)
10^-9 (0.000000001)
ch 1. pico- (p)
10^-12 (0.000000000001)
ch 1. why are measurements always uncertain?
instruments have their flaws
Measuring always involve estimation
All measurements have certain or exact digits, uncertain or estimated digits
Symbol for uncertainty in measurement is…
±
ch 1. leading zeros
never significant ex) 0.00012 = 2 significant figures
ch 1. captive zeros
always significant ex) 2.003 = 4 significant figures
ch 1. trailing zeros
only significant if there is a decimal ex) 600 = 1 significant figures
ch 1. nonzero integers
always significant ex) 3453 = 4 significant figures
ch 1. Rules for Multiplication and Division of Significant Figures
leave your answer in the same number of significant figures as the number with the least significant figures ex) 4.36 x 1.2 = 5.232, Answer = 5.2
ch 1. Rules for Addition and Subtraction of Significant Figures
Leave your answer in the same number of decimal places as the measurement with the least decimal places ex) 12.11 + 18.0 + 1.013 = 31.123 Answer = 31.1 (because 18.0 has 1 decimal place)
ch 1. density equation
D=M/V
ch 1. volume equation
V=M/D
ch 1. mass equation
M=DV
ch 1. what are the two factors to determine reliability in measurement?
precision and accuracy
ch 1. precision
Degree of agreement among many measurements of the same quality
ch 1. accuracy
How close a measurement is to the accepted value
ch 1. scientific notation
short way of writing a very large number or measurement
ch 1. percentage error
% error = value accepted-value expected/value accepted x 100
ch 1. dependent variable
a variable whose value depends on that of another
ch 1. independent variable
a variable whose value doesn't depends on that of another
ch 1. pure substance
a pure substance is one with a fixed or constant composition
ch 1. elements
a pure substance made of one kind of atom & cannot be broken down into a simpler substance by any chemical or physical process
ch 1. compound
made up of two or more different elements or atoms chemically bonded together
A Pure Substance with a fixed composition
ch 1. mixtures
a blend of two or more substances that aren't chemically bonded
ch 1. homogeneous mixtures
you cannot see the different parts of the mixture
ch 1. heterogeneous mixtures
you can see the different parts of the mixture
ch 1. methods for separating mixtures
Filtration (Ex. The Sand & Filter Paper)
Evaporation (Ex. The Salt In The Water Lab)
Distillation (Differences in Boiling Points)
Crystallization (the impure substance is dissolved in water, then filtered, then heated slowly, then cooled slowly leaving pure crystals formed without impurities)
Chromatography (Composition Moves @ Different Paces)
Magnetization ( Magnetic Material vs Non-Magnetic Material ) Ex. Iron & Magnet
Ddecantation ( Liquid vs. Solid ) Ex. Pasta & Water
Electrolysis - CHEMICAL PROCESS (Ex. Hydrogen Atoms from Oxygen Atoms in Water)
ch 1. types of energy
mechanical energy, potential energy, kinetic energy
ch 2. physical property
observable characteristics of matter in which no new matter is formed
ch 2. chemical property
observable characteristics of matter in which a new substance is always formed
ch 2. physical change
no new matter is formed
ch 2. chemical change
new matter is always formed
ch 2. what are some evidences of a chemical change?
formation of gas or bubble
changes in temp.
formation of precipitate
color change
ch 2. what are the states of matter?
gas, liquid, solid, plasma
ch 2. conduction
the transfer of thermal energy by the collision of particles when objects or substances are in contact
ch 2. convection
process by which heat is transferred by movement of a heated fluid such as air or water
ch 2. radiation
a mode of energy transfer that occurs when thermal energy is transferred through waves
ch 2. open system
matter and energy can flow into or out of the system through its boundaries
ch 2. isolated system
matter and energy do not flow into or out of an isolated system
ch 2. closed system
energy may cross the system boundaries but matter cannot
ch 3. who discovered the electron?
JJ Thomson
ch 3. who discovered the proton?
Ernest Rutherford
ch 3. who discovered the neutron?
James Chadwick
ch 3. who created the Law of Conservation of Matter/Mass?
Antonine Lavoisier
ch 3. Law of Conservation of Matter/Mass
states that matter cannot be created nor destroyed
ch 3. who created the Law of Constant Composition?
Joseph Proust
ch 3. Law of Constant Composition
states that a given compound always has the same elements in the same proportions
ch 3. Dalton's Atomic Theory
each element is made up of tiny particles called atoms
atoms of a given element are identical
chemical compounds are formed when atoms of different elements combine with each other
ch 3. JJ Thomson's model of atom
concluded that atoms have negatively charged particles or electrons. But atoms are electrically neutral. Meaning they must have equal negative and positive charges
ch 3. Rutherford's model of the atom
concluded that an atom's positive charge and most of its mass are in the center of the atom called the nucleus with negatively charged electrons moving around the nucleus and its empty space
ch 3. Bohr's model of the atom
atom is a small positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus
ch 3. Modern Atomic Theory
an atom contains protons, neutrons, and electrons
ch 3. the charge of a proton
positive
ch 3. the charge of a neutron
no charge
ch 3. the charge of an electron
negative
ch 3. location of a neutron
in the nucleus
ch 3. location of an electron
outside of the nucleus
ch 3. location of a proton
in the nucleus
ch 3. atomic number
the number of protons in an atom
ch 3. mass number
the sum of protons and neutrons in an atom or protons and neutrons (has no decimals)
ch 3. atomic mass/weight
the average mass of the relative abundance of the isotopes of an element (has decimals as seen in the periodic table)
ch 3. isotopes
atoms with the same number of protons but different numbers of neutrons
ch 3. atom's charge when it loses electrons
positive
ch 3. atom's charge when it gains electrons
negative
ch 3. where is mass number labelled on an ion?
top left
ch 3. where is atomic number labelled on an ion?
bottom left
ch 3. where is the electron and its charge labelled on an ion?
top right
ch 4. amplitude
height of wave measured from origin to crest, or peak
ch 4. wavelength
distance between successive crests of wave; distance that wave travels
ch 4. frequency
tells how fast the wave oscillates up and down
ch 4. hertz (Hz)
cycle per second
ch 4. speed of light
light moves through space at 3.00 x 108 meters per second
ch 4. visible spectrum
array of colors
ch 4. wavelength formula
λ = c / v (wavelength = speed of light / frequency)