Ionic bonding Flashcards
What are the properties of salts (ionic compounds)?
High melting and boiling points, brittle, soluble in water, only conduct electricity when melted or dissolved in water
What is the perfect ionic model?
All salts are made of positive and negative ions arranged in a 3D lattice, and that these ions are all perfect spheres. Overall charge of the salt is zero
What keeps the lattice together?
Ionic bonding - the electrostatic attraction between all positive and negative ions in a lattice
Charge of group 1 cations?
1+ (just write plus)
Charge of group 2 cations?
2+
Charge of Aluminium (Al) cations?
3+
Charge of Silver (Ag) cations?
1+ (just write plus)
Charge of Zinc (Zn) cations?
2+
Charge of Iron (Fe) cations?
2+ / 3+
Charge of Copper (Cu) cations?
1+ / 2+
Charge of Lead (Pb) cations?
2+ / 4+
How do you name anions?
Change ending to -ide e.g. sulfide
What is a polyatomic ion?
Ions made of more than one atom
How are sulfate ions represented?
SO4^2-
How are hydroxide ions represented?
OH-
How are nitrate ions represented?
NO3^-
How are carbonate ions represented?
CO3^2-
How are ammonium ions represented?
NH4^+
How do you represent ionic compounds?
In the ratio that they combine in to get to a neutral charge (as subscripts)
How are ionic compounds (bonding) formed?
____ electron/s is transferred from one (metal atom) to one (non-metal atom)
Why do ionic compounds conduct electricity when molten or dissolved?
Ions in a liquid are free to move around and they can carry a charge. In a solid the ions are strongly bonded in place, so cannot carry charge and conduct electricity
What happens when you boil ionic compounds?
Ions separate into pairs, cannot carry charge and can’t conduct electricity
Why do ionic compounds have high melting and boiling points?
There is a strong electrostatic attraction between cations and anions. Lots of energy is needed to overcome this attraction
How does charge affect the strength of ionic bonding?
The larger the charge of ions in the lattice, the stronger the electrostatic attraction so the stronger the ionic bond
How does distance affect ionic bonding?
The larger the distance between ions in the lattice, the weaker the electrostatic attraction so the weaker the ionic bonding
How do you compare the size of ions?
The larger the distance between the nucleus and outer shell of electrons, the larger the ion
What happens to the size of ions down a group?
Increases
How do you compare melting/boiling points of ionic compounds?
Compare size and charge of ions
Why are ionic compounds brittle?
When the ions are forced out of position, like charges line up and cause repulsion, cracking the ionic compound
