C2 Chemistry Flashcards
Metal atoms and non metal atoms
Metal atoms lose an electron at their highest level to be positively charged ions
Non metal ions gain an electron to become negatively charged ions
What are ions?
Ions are electrically charged particles formed when they lose or gain electrons
Ionic bonding
Metal reacts with a nonmetal, electrons are transferred from the metal to the nonmetal atoms that forms ions
An ionic bond is the electrostatic force of attraction between oppositely charged ions.
covalent bonding
When 2 nonmetal atoms share a pair of electrons
Double or triple covalent bond means?
They share 2 pairs of electrons or 3
Simple molecular substances
Atoms joined by stronger covalent bonds
Held by weak intermolecular forces making them have low boiling and melting points
They do not conduct electricity
Giant covalent structures
Atoms joined together by covalent bonds to form a giant lattice.
They have high melting and boiling points
Graphite
Have carbon atoms in layers, that each of them is joined to three other carbon atoms.
Atoms can slide over each other that makes it soft because there are no covalent bonds between them.
It conducts electricity
Diamond
Diamond is very hard and have a high melting point but does not conduct elected him because each carbon atom is joined to 4 other carbon that forms a giant covalent structure
Silica
Hard and has a high melting point
It’s similar to diamond however it has silicone and oxygen atoms instead of carbon atoms
Ionic compounds
Conduct electricity when in solution and molten but not in solid form because their atoms cannot move in their lattice structure
Why are metals malleable?
They have atoms in form of layers and these layers life over each other when bent
Why are alloys harder than pure metal?
They have different sizes of atoms that distort the regular arrangements of the atoms, so this makes it harder for the layers to slide over
Work out Mr
Add the relative atomic mass Example 1 Find the Mr of carbon monoxide, CO Mr = 12 + 16 = 28 Example 2 Find the Mr of sodium oxide, Na2O Mr = (23 × 2) + 16 = 46 + 16 = 62
Work out moles
The amount of grams of a specific substance is divided by the Mr.
Eg, carbon monoxide Mr is 28
14 g of carbon monoxide contains 14 ÷ 28 = 0.5 moles
56 g of carbon monoxide contains 56 ÷ 28 = 2
