Chemistry Unit 1 Flashcards
Define: Matter
anything that takes up space and mass
Define:Mixed substance or Mixture
made up of components not found on the periodic table i.e. a mixture
Define: Heterogeneous Micture
a mix f substances that have 2 or more phases (appears as more than one thing)
Define: Homogeneous Mixture
a mix of substances that have one phase and therefore it looks uniorm
Define: Pure Substance
made up of only type of atom found on the periodic table. It contains 1 phase and is homogeneous
Define: Element
only one particle that cannot be broken down any further and is straight off the periodic table
Define: Compound Molecule
contains two or more elements that move as a single unit
Define: Atom
the smallest particle of matter
Define:Atomic Theory
a theory describing the structure, behavior and other properties of an atom and it components/parts
Define: Proton
a subatomic particle that has a charge of +1, a mass of 1 amu and is found in the nucleus
Define:Neutron
a subatomic particle that has a neutral charge, has a mass of 1 amu and is found in the nucleus
Define: Electron
a subatomic particle that has a charge of -1, has a mass of approx. 0 amu and is found orbitting the nucleus in shells
Define:Nucleus
the very dense center of an atom which contains the protons and the neutrons of the atom.
Define:Shells
The rings around the nucleus where electrons orbit the nucleus and can be exchanged or shared among atoms
Define:Bohr-Rutherford Diagram
a diagram created to show the atom with its nucleus and all its electrons on their shells
Define: Valence Electrons
the electrons on the outermost shell. They are the extra or lacking atoms sitting on the outer shell.
Define: Valence Shell
the outermost shell in an atom containing electrons
Define: Periodic Table
a way of organizing all the elements in a realistic way where they can be organized by re-activity, state and mass
Define: Period
the horizontal rows on a periodic table
Define: Group / Family
the vertical columns in the periodic table. Elements of the same group have the same number of valence electrons
Define:Metal
conduct electricity well. These include all elements to the left of the “staircase” excluding hydrogen
Define: Non-metal
do not conduct electricity well and act as insulators. These include all elements to the right of the staircase plus hydrogen
Define: Metalloid/Semi-Metal
have properties of both metals and non-metals. They are the elements that make up the staircase
Define: Alkali Metal
are highly reactive because the atom is unstable. They have 1 valence electron so they lose one electron and have an overall charge of +1
Define: Alkaline Earth Metals
are reactive because they have 2 valence electrons so they lose 2 electrons to have an overall charge of +2
Define: Halogen
highly reactive non-metals because they have 7 valence electrons therefore they only need to gain one electron so they will gain 1 electron to have a charge of -1
Define: Noble Gas
gases that are very unreactive because they already have a full shell therefore cannot gain or lose electrons
Define: Atomic Number
is the number of protons or electrons
Define: Atomic Mass or Mass Number
the number of protons plus the number of neutrons
Define: Ion
an atom that has gotten an electric charge from gaining or losing electrons
Define: Anion
an ion that has gained electrons to have a negative charge (since all atoms start with a neutral charge)
Define: Cation
an ion that has lots electrons t have an overall positive charge
Define: Chemical Property
are those observed when a substance undergoes a chemical reaction.
Define: Physical Property
are those that can be observed without chemically changing a substance. Ex. state, melting point, solubility, colour, odour, texture, etc.
Define: Reactant
the elements and/or compounds that go into a chemical reaction
Define: Product
the compounds/elements that are created by a chemical reaction
Define: Chemical Equation
a representation of a chemical reaction by showing the reactants by their symbol and the products
Define: Word Equation
a chemical reaction expressed in words rather than elemental symbols
Define: Skeleton Equation
an equation that identifies the reactants and products but does not quantify them
Define: Balanced Chemical Equation
an equation that identifies the reactants and products and also quantifies them so the number of atoms on both sides is equal
Define: Law of Conservation of Mass
states that mass can not be created or destroyed so what goes into a chemical reaction must also come out of it as a product
Define: Ionic Compound
a bond between a metal and a non metal where electrons are exchange so each ion has a full outer shell. They are held together because they have attracting (opposite) electrostatic charges
Define: Multivalent Element
a metal element that can create more than 1 ion. Ex. iron can become Fe +2 or Fe+3
Define: Polyatomic Ion
compounds of elements that act and work as a single unit. They consist of more than 2 elements, have no “ide” endings and are mainly negative
Define: Covalent Compound
a bond between 2 non-metals where the electrons are shared between the atoms. They are held together by the shared electrons.
Define: Diatomic Molecule
non-metal elements that naturally exist in pairs ex. H2
Define: pH Scale
The scale that acids and bases are measured on. if a substance has a pH of less than 7 it is acidic, if the pH is 7 then it is neutral and if the pH is more than 7 it is basic
Define: Neutral
is the value of 7 on the pH scale
Define: Acid
has a value of less than 7 on the pH scale. This means that the substance has a sour taste, turns blue litmus paper red and contains hydrogen
Define: Base
a substance with a pH of more than 7 on the pH scale when the substance is in an aqueous solution
Define: Acid-Base Indicator
it is usually a strip of paper that changes colour when an acid or base is present
Define: Precipitate
an insoluble solid that forms from a liquid solution
Define: Synthesis Reaction
a reaction in which 2 elements combine to forma compound. Ex. element+element=compound
Define: Decomposition Reaction
a reaction in which a compound breaks up to become separate atoms. Ex. Compound=element+element
Define: Combustion Reaction
a reaction in which a fuel rapidly combines with oxygen to produce carbon dioxide+water (or carbon monoxide+water if it is an incomplete combustion)
Define: Single Displacement Reaction
a reaction in which an element reacts with an ionic compound where the element replaces one part of the compound and leaves an element by itself. Ex. A+BC=AB+C
Double Displacement Reaction
a chemical reaction in which the positive or negative ions in 2 ionic compounds switch places. Ex. AB+CD=CB+AD
Define: Neutralization
a reaction between an acid and a base to produce a salt (ionic compound) and water. This balances the pH level and brings it closer to 7.
What are the steps to writing the formula from the name of a Ionic Compound?
- look at the charges of both elements
- write down the metal ion’s symbol, then the non-metal
- apply the cross over rule and reduce if possible
What are the steps to writing the name from the formula of an Ionic Compound?
- write the name of the metal
- write the name of the non-metal
- change the ending of the non-metal to “ide”
* If there is a polyatomic ion instead of a non-metal, the ending does not change to “ide.”*
What are the steps to write the name from the formula of a Multivalent Ionic Compound?
- write the name of the metal
- write the name of the negative ion (non-metal or polyatomic ion)
- place Roman numerals for te correct charge between the elements
(To find the Roman Numeral: - find the et charge of the non-metal
- divide the net charge by the num,ber of multivalent atoms
- place the result in roman numerals)
What are the steps to write the formula from the name for Multivalen Ionic Compounds?
- find charges for both parts (roman numerals are teh charge for the metal)
- write both symbols
- apply cross over rule and reduce
What are the steps to write the name from the formula of a Covalent Compound?
- write the first element (if there are more than 1 of that atom, put the correct prefix)
- write the second element with the correct prefix
What are the steps to write the formula from the name of a Covalent Compound?
- write the symbol for the first element (if there us a prefix write out the correct number)
- write the symbol for the second element with the right number from the prefix
What are the prefixes used in Covalent Compounds?
1- mono 2- di 3- tri 4- tetra 5- penta 6- hexa 7- hepta 8- octa 9- non 10- deca
What are the things to remember when writing chemical equations?
- remember diatomic elements if they are by themselves
- you can’t change subscripts- only add numbers infront of elements
- always keep states at the end of each compound and balanced equations
What are the properties of Acids?
- taste sour
- don’t feel slippery
- pH less than 7
- blue litmus paper turns red
- releases Hydrogen atoms in aqueous solution
- corrodes metals
- reacts with metals to produce a compound plus hydrogen gas
- their chemical equation starts with hydrogen or ends with COOH
What properties do both acids and bases share?
- both dissolve in water
- both conduct electricity
- both burn and irritate your skin
What are the properties of Bases?
- taste bitter
- Feel slippery
- pH greater than 7
- red litmus paper turns blue
- release hydroxide ions in aqueous solution
- do not corrode metals
- do not react with metals to produce a compound and hydrogen gas
- their chemical equation starts with a metal ion or ammonium and ends with hydroxide (OH)
What is Neutralization and when does it occur?
- occurs when an acid reacts with a base to produce a salt and water
- it balances the pH and moves it closer to 7
What are the steps to name acids?
- start with “hydro” (since it always starts with hydrogen)
- add non-metal and change ending to “ic”
- add the word “acid” after