Chem - the periodic table and bonding

Question 1

Charges of ions: Iron, lead, copper, zinc, silver, hydrogen, hydroxide, ammonium, sulfate, nitrate, coarbonate

Answer 1

Silver: Ag+
Copper: Cu2+
Iron: Fe2+, Fe3+
Zinc: Zn2+
Lead: Pb2+
Hydrogen: H+
Hydroxide: OH-
Ammonium: NH4+
Carbonate: CO32-
Nitrate: NO¬3-
Sulfate: SO42-

Question 2

What is ionic bonding

Answer 2

Ionic bonding: forms when a metal and a non-metal react together 
Metals usually lose an electron to the non-metal(s) and becomes a positively charged ion (cations), non-metals usually gain an electron from the metal and becomes a negatively charged ion (anions)
Group 1 (metal) = 1 electron on outer shell ; therefore it loses the electron to gain a full outer shell
Group 7 (non-metal) = 7 electrons on outer shell ; therefore it gains an electron to gain a full outer electron shell

Question 3

ionic compounds

Answer 3

Giant ionic structure
Ions held together in closely packed Lattice structure
Strong forces of attraction between oppositely charged ions, requires a lot of energy to overcome, therefore high melting and boiling points
Cannot electricity when solid as it has fixed lattice structure, no free electrons
Can conduct electricity when molten or dissolved in water as there will be free electrons

Question 4

What is covalent bonding

Answer 4

Occurs between two non-metals

strong electrostatic attraction between negatively charged shared electrons and the nuclei of the atoms.

Question 5

Simple molecular substance

Answer 5

Atoms are held together by strong covalent bonds
Weak intermolecular forces between the atoms, low melting and boiling points, does not require a lot of energy to overcome as molecules can be easily separated

Question 6

Giant covalent strucutres

Answer 6

All atoms bonded together by strong covalent bonds, requires a lot of energy to overcome, therefore has a high melting and boiling point.
Cannot conduct electricity (except for graphite) as it has a giant fixed lattice with many covalent bonds

Question 7

Giant covalent - diamond

Answer 7

Giant covalent strucutres

Question 8

Giant covalent - graphite

Answer 8

Graphite: layers of atoms with weak intermolecular forces attracting the layers to each other, good conductor of electricity and good malleability as these layers of atoms can slide over each other. Only 3 electrons are used in bonding so the Carbon atom can also have a delocalized electron which increases conductivity. Strong covalent bonds within the layers require lots of energy to break - high melting and boiling points.

Question 9

Metallic bonding

Answer 9

Strong forces of attraction between positively charged ions and a sea of delocalized electrons - high melting and boiling points. Delocalized electrons are free to move through the structure allows for good electrical conductivity and good heat conductivity as the energy can be transferred quickly through them.

Layers of ions can slide over each other - good malleability