Unit 1 Test - Part 1 Flashcards
Physical Property
What the substance is like - Using the 5 senses and measurements
Chemical Property
Describes how a substance behaves - a new substance formed
Physical Change
A change occurs but no new substance is produced.
Chemical change
A new substance with new properties is formed.
Matter Classification
Matter Classification
Mixtures and Pure substances
Homogenous mixtures (uniform) Elements
Heterogenous mixtures (visibly different) Compounds
Element
Building blocks of matter
Compounds
When two or more elements combine
Solutions
Mixed throughout
Mixtures
Two or more substances can be seen
Solute
The one that is being dissolved
Solvent
The one doing the dissolving
Particles
Proton- +charge - in the nucleus - heavy
Neutron - neutral charge - in the nucleus - heavy
Electron - - charge - the orbit - light
For Bohr Rutherford diagrams
of protons = Atomic number
# of electrons = number of protons
# of neutrons = difference between mass and atomic number
Lewis diagrams
Just the chemical name and valence electrons (outside ring electrons)
Atom
Simplest from of an element
Pure substance
matter that can’t be divided
Qualitative Analysis/Observation
Observing the physical qualities.
Quantitative Observation
The amount of a substance
Atomic Mass
Mass of an element
Atomic number
the number of protons
Energy level
the ring electrons are on
Group
A COLLUMN on the periodic table
Period
A ROW on the table
Halogens
Non-metalic elements to the right of the staircase
Ion
An element that has has 1 or more negative or positive charges
Isotope
2 or more atoms that have the same number of protons but different neutrons
metalloid
Metal-like elements on the staircase
Noble gas
Group of gaseous elements at the far right of the table
Diatomic molecule
Molecule containing 2 stoms chemically bonded
Ionic Compound
Compounds made up of ions that formed charged particles when an electron is gained or lost
Covalent compound
Molecule formed by covalent bonds, the atoms will share one or more pairs of valence electrons
Bonds
Ionic- bond between a metal and non-metal
Molecular - Bond between non-metals
Empirical knowledge
knowledge through observations
theoretical knowledge
knowledge based on ideas created to explain observations
Observation
Something you can detect with your senses
Inference
something you know or think you know.
Atomic theory 450-400 BC - Empedocles and Democritus
Empedocles - Believed there were 4 elements Earth, Wid, Fire and Water, produced by 4 properties dry, hot, wet and cold.
Democritus - First to suggest that matter is particles, matter could be divided smaller and smaller until not able, different atoms have different sizes and is in constant motion
Electromagnetic Spectrum
-Light travels in fast or slow waves
-Long waves (low frequency, low energy, not harmful, radiowaves)
-Short waves (high frequency, high energy, harmful, x-rays and UV)
- Visible light is in between
-Each colour has a different wavelength
-Each element has its own unique line spectra
-Different types of matter emit different wavelengths
Spectroscopy
-Spectroscopes are used to separate light and reveal different line spectra
-A line spectra analyses different types of matter
-Spectroscopy is used in:
- Water samples, Planetary atmospheres, hair, blood and urine tests for poison
Qualitative properties
State, colour, taste, odour, clarity, lustre, texture, for, hardness and viscosity
Quantitative properties
Boiling point, melting or freezing point, density, solubility, conductivity
Observation
Something you detect with your senses
Interpretation/inference
Something you know or think you know
Atomic theory -1809 - John Dalton
-Suggested matter consists of definite particles, atoms
- Elements are made up of its own identical particles
-Atoms of different elements have different properties
-Atoms of 2 or more elements can combine in constant ratios to form new substances
-Atoms can’t be destroyed created or subdivided in a chemical change
Atomic theory - 1897 - JJ Thomson
-Used a cathode ray tube
-Discovered subatomic particles in the atom
-negative particles later called electrons
Atomic theory - 1910 - Ernest Rutherford
-Discovered positively charged nucleus
-suggested negative electrons orbit the nucleus
-gold foil experiment (positively charged particles at centre)
-problem: electrons should give off energy, and eventually fall down (which doesn’t happen)
Atomic theory - James Chadwick
- Discovered neutrons
Atomic theory - 1913 - Niels Bhor
-Suggested electrons exist at various levels
-orbits farther out possess more energy
-Electrons can jump levels but not between them
-Increase in energy moves electron up, when it falls light is emitted
Orbitals/energy levels
-Where an electron spends its time
-1 or 2 electrons can occupy the same orbit (Pauli Exclusion Principle)
-Electrons fill low orbitals before they fill high ones
-When there is a choice they fill singly as far as possible
-Spin in opposite directions in the same orbit
Periodic Table groups
-Alkali metals (Na, K, Li)
-Alkaline Earth metals (Mg, Be, Ca)
-Halogens (F, Cl, Br)
-Nobles Gases (Ne, Ar, Kr)
-Transition metals (Fe, Co, Ni)
-Metalloids (B, Al, Si)
Lanthanides and Actinides (U, Np, Pu) (bottom rows)
Electronegativity
-The property of an element that attracts shared electrons.
-Periods- The EN increases
-Groups- The EN decreases
Atomic Radius
-The distance from the nucleus to the valence electrons
-Periods- The radius decreases
-Groups- The radius increases
Ionization Energy
-The amount of energy it takes to remove an electron
-Periods- IE increases
-Groups- IE decreases
Radioactivity on Periodic Table
Bottom left to upper right
- The number of electrons
-The smaller the number of electrons transferred the more vigorous the reaction
Polarity
Non-polar covalent - equal distibution
Polar covalent - non-equal distribution
Ionic bonds will always be polar.
Shapes
-Linear
-Trigonal Planar (flat triangle)
-Angular ( 2 bonds, 2 extra electrons)
-Tetrahedral (For bonds)
-Pyramidal (3 bonds, 2 extra electrons)
