chemistry Flashcards
Define WHMIS
Workplace hazardous materials information system
What does MSDS stand for
Material Safety Data Sheets
Define physical change
A change that changes the substance without changing its composition.
Whats a physical property?
Things we can observe with our senses (eg how it looks, feels)
What are some physical properties?
- boiling/ condensation point
- melting/freezing point
- malleability
- ductility
- colour
- solubility
7.crystal formation - conductivity
- state
- magnetism
What is a chemical change?
Creating a new substance with new properties
Define chemical property
How it reacts with another substance
What are some chemical properties?
- ability to burn
- flash point
- reaction with oxygen
- reaction with water
- reactions with acids
- reactions with heat
- reactions to litmus
define pure substance and name the types of pure substances
Pure substances are substances that only contain one kind of matter and cannot physically be broken down any further. They can be elements or compounds.
Define mixture and give the types of mixtures
A mixture is a substance made of 2 or more pure substances. Mixtures are separated into heterogeneous and homogeneous mixtures. Within the heterogeneous mixtures there are mechanical mixtures, suspensions and colloids, in the homogeneous mixtures there are solutions.
Whats an atom?
The building blocks of matter. They cannot be broken down into simpler substances.
Whats an element?
Elements are the names we give atoms with specific properties
What are molecules?
Molecules are groups of atoms bonded together. These may be atoms of the same element
Define compound
Compounds are chemical substances in which two or more DIFFERENT elements are bound together
Whats the atomic number
The number of protons
Whats the atomic mass
the sum of the protons and neutrons
How do you find the number of neutrons
Since the atomic mass is the sum of protons and neutrons you would take away the amount of protons (atomic number) from the mass
What are the charges of protons neurons and electrons?
Protons have a charge of +1
neutrons have a charge of 0
electrons have a charge of -1
How do you find the number of electrons?
Since the number of electrons=the number of protons you use the number of protons. For example if there are 6 protons there are also 6 electrons
What information do we get off of the periodic table?
An elements mass, each elements name and symbol, the amount of protons neutrons and electrons, its state at room temp and whether its a metal, non-metal or metalloid.
What are characteristics of metals?
- have a shiny, metallic lustre
- good conductors of heat and electricity
- malleable and ductile
- solid at room temp (except mercury)
What are some characteristics of non-metals?
- dull
- don’t conduct heat well, do not conduct electricity at all
- any state at room temp
What are some characteristics of metalloids ?
- characteristics of both metals and nons
- often brittle solids
- conduct electricity but not as well as metals
Whats an ionic vs molecular compound
ionic is metal + non metal
Molecular is non metal + non metal
define valance
the electron/trons on the outer most shell
what is reactivity caused by
the valance
what are ions
Ions are atoms that have lost or gained electrons, resulting in either a positive (+) or negative (-) charge.
what are anions
Anions are negatively charged (results from a gain of electrons)
what are cations
Cations are positively charged (results from a loss of electrons)
are metal atoms positive or negative
Metal atoms lose electrons to become positively charged cations
are nonmetal ions positive or negative
non metal ions gain an electron to become negatively charged anions
What are some properties of ionic compounds
- high melting/boiling points
- solid at room temp
- dissolves in water
- when dissolved in water, it will conduct electricity
- Form crystal lattices not molecules
how do you name an ionic compound?
the name of the metal roman numerals of what charge your using(if there’s more than one) name of non metal and replace the ending with ide.
whats a polyatomic ion?
Polyatomic ions are a group of atoms combined together that exist as a single unit and have a charge.
whats group 1 on the periodic table
Group 1 – is divided into hydrogen and the alkali metals. These are the most reactive metals and they react violently in air or water. Reactivity increases as you move down the group. they react best with the halogens
what is group 2 on the periodic table
Group 2 – are the alkaline-earth metals. These metals also react with air and water, but are less reactive than alkali metals.
what is group 17
Group 17 – are the halogens and are the most reactive of the non-metals. They tend to combine with other elements to make compounds.
what is group 18
Group 18 – are the noble gases and are the most stable and unreactive of the elements.
Why are ionic compounds solid at room temperature?
Ionic bonds are really strong, it takes lots of energy to break them
