COMPOUND ;) Flashcards
(35 cards)
COMPOUND
2 or more elements whose atoms are chemically combined in a fixed proportion.
Compounds are named due to the elements within them
Compound names are based upon….
The elements that are within them
The suffix “-ide” is added to the compounds name in which scenario:
A) the compound has a metal in it]
B) the compound is a compound and not hydrogen,
C) The compound has oxygen within it.
B) the compound is a compound and not hydrogen,
“The suffix “-ate” is added onto a compounds name when the compound contains oxygen (O).” True or false evaluate the sentence, how far do you agree with the statement?
Very far, this is correct!
Elements could be completely different from the compounds which they form
E.g. Compound of Carbon and 2 oxygen is not the same as carbon or oxygen on their own.
Define. “Mono” in the form of a compound
“Mono” is used in front of a compound’s NON-METAL name and means 1, there is 1 of the following atom. Use this (1) only when necessary e.g. carbon monoxide, in this case, would be the same as carbon dioxide, if we did not put -di or -mono in front of oxide, don’t use this much.
EXAMPLES:
- Carbon monoxide (oxygen is a non-metal so is put after carbon (a metal) it’s necessary to put mono.
What do “-di, - tri, -tetra”, -“penta”, -“hexa”,and possibly “septa” mean in terms of compounds.
*REMEMEBER: ONLY USE THESE BELOW ON A NON-METAL AND USE WHEN YOU CAN! NOT LIKE -MONO!”
Di- 2
Tri - 3
Tetra - 4
Penta - 5
Hexa - 6
Septa? - 7?
RULES OF NAME OF COMPOUNDS (-IDE)
2, ONLY 2 elements present = end of the name of 2nd element changed to -ide, e.g. Sulph-ur- to sulPHIDE.
Copper sulphide = CuS
RULES OF NAMES OF COMPOUNDS: METAL BEGINNING OR END?
1, If a METAL is present in the compound, it goes at the BEGINNING.
RULES OF THE NAME OF A COMPOUND: -ate and excpetions
3, if compound contains:
(1), metal
(2), hydrogen
(3), oxygen
ONLY then it is called: metal hydroxide!
****ALTHOUGH, OXYGEN + ELEMENT = ELEMENT ENDING IN —ATE, OXYGEN +HYDROGEN = HYDROXIDE
Remember!
Sodium, hydrogen and oxygen = sodium hydroxide!
.
Sodium + bromine = ?
aluminium + iodine = ?
Cu + S + O = ?
Ca + C + O = ?
Lithium, nitrogen
Sodium bromide
Aluminium iodide
Copper sulfate
Calcium carbonate
NAMES OF COMPOUNDS
Metal + boron—> Metal borIDE
Metal + boron + oxygen —> Metal borATE
Metal + Hydrogen —> Metal hydriDE
Metal + hydrogen + oxygen —> Metal hydroXIDE
Metal + Carbon —> Metal carbIDE NOT CARBONIDE
example = REACTANTS
example = PRODUCTS
magnesium + oxygen —> Magnesium OXIDE.
OBSERVATIONS:
MUST include state and colour, e.g.
Q) What were your observations in experiment 6.0 with Copper, oxygen adn copper oxide?
A) my observations from experiment 6.0 were that copper (a shiny red-brown solid) and oxygen (a colourless gas) are completely different elements to copper oxide (black/red powder).
DIFFERENCE BETWEEN COMPOUNDS AND THE ELEMENTS WITHIN THEM:
SEE CHEMISTRY - COMPOUNDS (2ND FORM)
MOLECULE:
Certain compounds contain groups of atoms, which from together, these are called MOLECUES
In a compound the atoms of the different elements are present in a
X) Varied ratio,
M) Fixed ratio.
M) FIXED RATIO
NAMING OF COMPOUNDS - SYMBOLS:
Molecule of compound will ALWAYS have same number of atoms of each element, which are joined together in the same way.
EXAMPLE: Carbon monoxide = compound of carbon & oxygen, this is made of molecules which ALWAYS contains 1 carbon joined to 1 oxygen ATOM Carbon dioxide = compound of carbon & oxygen too, made of molecules which ALWAYS contain 1 carbon joined to 2 oxygen ATOMS. If it had 1:1 ratio of carbon: oxygen it would be carbon MONOxide.
SYMBOLS FOR COMPOUNDS 2
No. Atoms in compound - represented using a CHEMICAL FORMULA!!
CHEMICAL FORMULA:
* chemical symbol from each element present in compound, followed by subscript.
E.g. carbon dioxide (1 carbon atom, 2 oxygen atoms) = SEE CHEMISTRY - COMPOUNDS (2ND FORM) NEED TO DO.
How can we show the number of atoms in a compound?
Using chemical formula
What is the subscript?
It comes after the chemical symbol of a compound and shows how many atoms present in each molecule (if there is 1 - no need to write number ALTHOUGH carbon monoxide is exception to differentiate from carbon dioxide).
WHEN WRITING A CHEMICAL FORMULA, WHAT COMES FIRST:
-METAL,
-NON-METAL?
Metal!
What is the number of bonds a non-metal forms in the group 4?
The number of bonds a non-metal forms is based upon its group.
Rules that apply to non-metals:
Group 4 = 4 bonds per atom
Group 5 = 3 bonds per atom
Group 6 = 2 bonds per atom
Groups 7 = 1 bond per atom
HYDROGEN = 1 BOND PER ATOM
8-GROUP NUMBER = BONDS PER ATOM E.G. 8-5=3
