highschool/Grade 9/Science/SNC1DZ/Unit_2_Chemistry_Study_Sheet.md

Unit 2: Chemistry

Chemistry Vocabulary List

Word	Definition (or diagram/translation)
Particle Theory of Matter	Theory that describes the composition and behaviour of matter as being composed of small particles with empty space
Matter	Substance that has mass and occupies space
Mechanical Mixture	A heterogeneous mixture which one can physically separate
Suspension	A heterogeneous mixture where insoluble solid particles are distributed throughout a fluid, floating freely/td>
Alloy	A combination of 2+ metals
Mixture	A substance that is made up of at least 2 types of particles
Qualitative property	A property of a substance that is not measured and doesn’t have a numerical value, such as colour, odour, and texture
Qualitative observation	An numerical observation
Precipitate	A solid that separates from a solution
Density	A measure of how much mass is contained in a given unit volume of a substance; calculated by dividing the mass of a sample of its volume (mass/volume)
Element	Element An element is made up of the same atoms throughout, and cannot be broken down further
Metal	a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity
Pure substance	A substance that is made up of only one type of particle
Atom	The smallest unit of matter found in substances
Solution	A uniform mixture of 2 or more substances
Colloid	is substance with small particles suspended in it, unable to be separated by gravity
Emulsion	A mixture of 2 insoluble liquids, in which one liquid is suspended in the other
Physical Property	Characteristic of a substance that can be determined without changing the makeup of the substance
Characteristic	A physical property that is unique to a substance and can be used to identify the substance
Periodic Table	a table of the chemical elements arranged in order of atomic number, usually in rows, so that elements with similar atomic structure (and hence similar chemical properties) appear in vertical columns.
Compound	Compounds are chemically joined atoms of different elements
Non-Metal	A substance that isn’t a metal
Physical Change	A change in which the composition of the substance remains unalteredandno new substances are produced
Chemical Change	A change in the starting substance and the production of ONE or more new substances Original substance does not disappear BUT the composition is rearranged
Molecule	Two or more non-metal atoms joined together
Diatomic Molecules	Molecules that only consists of 2 elements H O F BR I N CL - hyrodgen, oxygen, fluorine, bromine, iodine, nitrogen, chlorine.
Ions	A Charged particle, that results from a loss (cation - positve, less electrons) or gain (anion - negative, more electrons) of electrons when bonding
Electron	Negatively Charged
Proton	Positively Charged
Neutron	Neutral Charged
Ionic Charge	The sum of the positive and negative charges in a ion
Covalent Bond	The sharing of electrons between atoms when bonding
Valence Electrons	Number of electrons on the most outer orbit/shell of the element

Particle Theory of Matter

1. Matter is made up of tiny particles.
2. Particles of Matter are in constant motion.
3. Particles of Matter are held together by very strong electrical forces.
4. There are empty spaces between the particles of matter that are very large compared to the particles themselves.
5. Each substance has unique particles that are different from the particles of other substances.

Physical Properties

• A characeristic of a substance that can be determined without changing the composition (“make-up”) of that substance
• Characteristics can be determinded using your 5 senses and measuring instruments
  • smell, taste, touch, hearing, sight
  • scales, tape, measuring meter

Qualitative and Quantitative Properties

Type	Definition	Example
Quantitative Property	A property that IS measured and has a numerical value	Ex. Temperature, height, mass, density
Qualitative Property	A property that is NOT measured and has no numerical value	Ex. Colour, odor, texture

Density

Quantitative physical Properties

• Density: amount of stuff (or mass) per unit volume (g/cm³)
• Freezing Point: point where water solidifies (0^oC)
• Melting Point: point where water liquefies (0^oC)
• Boiling Point: point where liquid phase becomes gaseous (100^oC)

Common Qualitative Physical Properties

Type	Definition	Example
Lustre	Shininess of dullness Referred to as high or low lustre depending on the shininess
Clarity	The ability to allow light through	Transparent (Glass) Translucent (Frosted Glass) Opaque (Brick)
Brittleness	Breakability or flexibility Glass would be considered as brittle whereas slime/clay are flexible
Viscosity	The ability of a liquid or gas to resist flow or not pour readily through Refer to as more or less viscous	Molasses is more viscous, water is less (gases tend to get”thicker as heated; liquids get runnier)
Hardness	The relative ability to scratch or be scratched by another substance Referred to as high or low level of hardness	Can use a scale (1 is wax, 10 is diamond)
Malleability	the ability of a substance to be hammered into a thinner sheet or molded	Silver is malleable Play dough/pizza dough is less glass is not malleable
Ductility	the ability of a substance to be pulled into a finer strand	Pieces of copper can be drawn into thin wires, ductile
Electrical Conductivity	The ability of a substance to allow electric current to pass through it Refer to as high and low conductivity	Copper wires have high conductivity Plastic has no conductivity
Form: Crystalline Solid	Have their particles arranged in an orderly geometric pattern	Salt and Diamonods
Form: Amorphous Solid	Have their particles randomly distributed without any long-range-pattern	Plastic, Glass, Charcoal

Chemical Property

• A characteristic (property) of a substance that describes its ability to undergo changes to its composition to produce one of more new substances. AKA BEHAVIOUR. Everything has one!
• Cannot be determined by physical properties
• E.g. ability of nails /cars to rust
• Fireworks are explosive
• Denim is resistant to soap, but is combustible
• Baking soda reacts with vinegar and cake ingredients to rise
• Bacterial cultures convert milk to cheese, grapes to wine, cocoa to chocolate
• CLR used to clean kettles, showerheads because it breaks down minerals
• Silver cleaner for tarnished jewellery, dishes because silver reacts with air to turn black.

Periodic Table

Trends On The Periodic Table

• The first column are the Alkali metals.
  • They are shiny, have the consitency of clay, and are easily cut with a knife.
  • They are the most reactive metals.
  • They react violently with water.
  • Alkali metals are never found as free elements in nature. They are always bonded with another element.
• The second column are the Alkaline earth metals.
  • They are never found uncombined in nature.
• The last column are the Noble gases.
  • Extremely un-reactive.
• The second last column are the Halogens.
  • The most reactive non-metals
  • They react with alkali metals to form salts.
• The middle parts are the transition metals.
  • They are good conductors of heat and electricity.
  • Usually bright coloured.
  • They have properties similar to elements in their same family
  • Many of them combine with oxygen to form compounds called oxides.
• The rows outside the table are the Inner tranistion metals.

• The left to the staircase are the metals and the right are the non-metals. The ones touching the staircase are the metalloids.

How To Read An Element

History of The Atom

Person	Description	Picture
Democritus	All matter can be divided up into smaller pieces until it reaches an unbreakable particle called an ATOM (cannot be cut) He proposed atoms are of diffent sizes, in constant motion and separated by empty spaces
Aristole	- Rejected Democritus ideas, believed all matter was made up the 4 elements, it was accepted for nearly 2000 years
John Dalton	- Billbard model, atoms of different elements are different Atoms are never created or destroyed. - Atoms of an element are identical
JJ Thomson	- Atoms contain negatively charged electrons, since atoms are neutral, the rest of the atom is a positevly charged sphere. - Negatively charged electrons were evenly distrubuted throughout the atom. - Ray cathode experiment - basically atoms were attracted to a postive end of the tube, so there most be negative charges in the atoms.
Ernest Rutherford	- Discovered that the postively charged nucleus. - The nucleus was surrounded by a cloud of negatively charged electrons - Most of the atom was just space. - Gold foil experiement, alpha particles (postively charged) shot at atom, some bounced off at weird angles, so there most be a postively charged thing there.
Niels Bohr	- Discovered that electrons orbit the nucleus in fixed paths, each electron has a definite amount of energy, further from nucles = more energy. - Electrons cannot jump orbit to orbit or release energy as light going down. - Each orbit can hold a specifc amount of electrons, 2,8,8,2, useful for the first 20 elements
James Chadwick	- Discovered the neutron, mass of neutron = mass of proton (basically) - Neutral atoms have equal numbers of protons and electrons.

Carbon

Atoms

• Subscripts - tells us how many of the atom are there, for example N₂ means there are 2 nitrongen atoms.
• Use distrubutive property if there are brackets and a subscript, for example, (CO)₂ is equilivant to C₂O₂.
• Atoms are stable if they have a full valence shell (noble gases)
• Each family has the same amount of valence electrons as their family number, so alkali metals would have 1 valence electron, alkaline earth metals will have 2, halogens will have 7 and noble gases would have 8.
• They will also have the same amount of protons as their atomic number.
• Number of protons = Number of electrons.
• Number of neutrons = mass - atomic number/number of protons.

Bohr-Rutherford / Lewis-Dot Diagrams

• Bohr-Rutherford
  • Draw nucleus, and draw the apprioate number of orbits.
  • Put number of protons and neutrons in the nucleus.
  • Draw the correct number of electrons in each orbit
• Lewis-Dot Diagrams
  • Draw element symbol
  • Put the right number of valence electrons around the symbol, perferably in pairs

Bonding

• To combine 2 atoms, each element wants to be stable. So they each want a full valence shell, (outer shell) so they are stable.
• They can either gain, lose or share electrons in order to become stable.
• Example:
  • Oxygen and Hydrogen, in order to become stable, they all need 8 valence electrons. Hydrogen has 1, oxygen has 6, so we bring in another hyrdogen and we let them share all their electrons, turning into H₂O, or water.
• Use arrows to show gaining or losing electrons.
• Circle to show sharing of electrons.

Naming of Ionic Bonds

1. Write cation (metal) first
2. Write anion (non-metal) second
3. Change the ending of the non-metal to ide.

Decomposition

• A chemical change used to break compounds down into simpler substances
• Energy must be ADDED
  • Using electricity
  • Adding thermal energy

Catalyst

• Substance that accelerates a chemical change without being consumed OR changed itself

Uses of Hydrogen Peroxide

• On cuts/scraps
  • Blood has a catalyst = see bubbling O₂
• Cleans contact lenses
  • Bubbling removes dirt
• Bleaches
  • React with compounds that provide color
  • RESULT = no colour (bleach blond hair/teeth)