Science Chemistry Grade 10 Unit Test Flashcards
What are ionic compounds?
Compounds that are made from metal and a non-metal ions which are attracted by positive charges.
How does an ion form?
An element loses or gains electrons.
What is the group of elements that are cations?
Usually metals
What is the group of elements that are anions?
Usually non-metals
How to name IONIC COMPOUNDS from formula?
- don‘t put in subscripts
- metal name first, non-metal name second
- change ending to „ ide“
How to write the formula for IONIC COMPOUNDS from the name?
- Write the symbols
- Write ionic charge above the element symbol
- Cross-multiply the charges
- Write the values as subscripts and reduce if there is a common factor.
What are multitalented metals?
Elements that are stable ions with more than 1 charge.
What are polyatomic ions?
An ion that is made up of a group of atoms that are bonded together and have a single net charge.
Polyatomic ions are made up of only non-metals
How to name POLYATOMIC IONS from the formula?
- Write the name of the metal.
- Write the name of polyatomic ion
- Write the valency of metal in brackets if needed
How to write the formula for POLYATOMIC IONS from the name?
- Follow cross-cross rule
- For the polyatomic ion, place it in the brackets before cross-multiplying.
- Write the subscripts and reduce if there is a common factor. Take the polyatomic ion out of brackets if the subscript is 1
What are molecular compounds?
Compounds that share electrons to form a covalent bond. Molecular compounds are formed from non-metals.
What is a covalent bond?
A bond in which atoms share electrons
What are diatomic molecules?
Two of the same atoms joined by a covalent bond
Name the diatomic elements
HOFBrINCl
When writing the formula, write them with a subscript of “2”.
How to name MOLECULAR COMPOUNDS from the formula?
Use prefixes for the subscript number:
1 - mono
2 - di
3 - tri
4 - tetra
5 - penta
The prefix -mono is dropped on the first atom.
When prefix is followed by oxide, “o” and “a” are dropped
Hydrogen doesn’t require a prefix unless it is an acid
How to write the formula for MOLECULAR COMPOUNDS from the name?
Write the symbols. use the prefix to write the subscript.
How to write a WORD equation for a reaction?
- Write the name of the elements
- Indicate their states of matter (s), (l), (g), (aq)
- Add the “ = “ and “+” signs
Lewis Dot Diagram
Contains the element symbol and # of valence electrons
Lewis Dot Diagram for Ionic compounds
- Write the symbols
- Draw the dots
- Show how electrons are transferred
- Put in brackets and write charge
Lewis Dot Diagram for Molecular compounds
- Draw the diagram for each element
- Circle the shared electrons
- Each shared pair is written as a bond. Draw a line for each shared pair instead of dots circled
Synthesis /Combination Reaction
A + B = AB
Reactant + reactant = 1 product
Decomposition reaction
AB = A + B
Single Displacement Reaction
A + MN = AN + M (if A is a metal) A + MN = MA + N (if A is a non-metal) M - usually a metal N - usually a non-metal Note: cations always go first
Double Displacement Reaction
AB + CD = AD + CB
First and last go together
inner go together
