Bonding and Calculations Flashcards
What will you find out from the Mass number?
The total number of protons and neutrons.
What will you find out from the Atomic number?
The number of protons.
Name the three different types of subatomic particles, their charge and where they are found in the atom.
Proton - Positive, found in the nucleus
Neutron - No charge, found in the nucleus
Electron - Negative, found in energy cells outside of the nucleus
What is a compound?
Something which is formed when atoms of two or more elements are chemically combined together.
What is an isotope?
Different atomic forms of the same element which have the SAME number of PROTONS but a DIFFERENT number of electrons.
Name an example of a pair of isotopes.
Carbon 12 and Carbon 14.
What happens in ionic bonding?
Atoms lose of gain electrons to form charged particles (ions). These ions tend to ‘latch’ onto oppositely charged ions.
Why do atoms take part in ionic bonding?
So that they can gain a full outer shell.
Name some examples of atoms that become positively charged ions.
Sodium, Potassium and Calcium are all examples.
Name some examples of atoms that become negatively charged ions.
Oxygen ad Chlorine are examples of atoms that gain electrons to become negatively charged overall.
What type of structure do ionic compounds have?
They have a regular lattice structure.
Name an example of an ionic compound and give its features.
Example: Sodium Chloride
Features:
- closely packed in a regular lattice
- Strong electrostatic forces of attraction between oppositely charged ions in all directions
Name the properties of an ionic compound.
Properties:
- High melting points (due to strong attraction between ions)
- High boiling points ( “ )
- When melted are able to carry an electric current
- Dissolve easily in water
What are the two pairs of groups that are most likely to form ions?
Groups 1&2 and 6&7.
What type of element are likely to give you positive ions?
Metals.
What type of element are likely to give you negative ions?
Non-metals.
Give a list of Positive ions.
Positive Group 1 Group 2 Li+ Be2+ N+ Mg2+ K+ Ca2+
Give a list of negative ions.
Group 6 Group 7
O2- F-
Cl-
What is the overall charge of an ionic compound?
The overall charge is zero as the positive and negative ions cancel each out.
Why is covalent bonding different from ionic bonding?
Ionic bonding is when atoms give electrons however covalent bonding is when atoms share electrons with each other.
When do atoms stop making covalent bonds?
When they have a full outer shell.
Name 7 examples of atoms that form covalent bonds.
- Hydrogen - H2
- Chlorine - Cl2
- Methane - CH4 (Carbon and Hydrogen)
- Hydrogen Chloride - HCl (Hydrogen and Chlorine)
- Ammonia - NH3 (Nitrogen and Hydrogen)
- Water - H2O (Hydrogen and Oxygen)
- Oxygen - O2
Name the 2 different types of covalent substances.
Simple molecular or Giant structure.
Name the features of a simple molecular substance.
Simple molecular substance:
- Very strong covalent bonds
- Very weak forces of attraction between the molecules
- Low melting and boiling points due to the weak intermolecular forces
- They don’t conduct electricity as there are no ions
Name the features of a giant covalent structure.
Giant covalent substance:
- Strong covalent bonds
- Very high boiling and melting points
- They don’t conduct electricity as there are no charged ions (graphite however is an exception when molten)
Name the features of Diamond.
Diamond features:
- each carbon atom forms 4 covalent bonds in a rigid giant covalent structure
- this structure makes diamond the hardest natural substance which is why it is used for drill tips
Name the features of Silicon Dioxide.
Features of Silicon Dioxide:
- structure which contains silicon and oxygen
Name the features of Graphite.
Features of Graphite:
- each carbon atom forms 3 covalent bonds
- this creates layers which are able to slide over each other (this is how the layers are able to appear on a page as a pencil marks they ‘have rubbed off’) due to the weak intermolecular forces present
- only non-metal which is a good conductor of heat and electricity as each carbon atom has one delocalised electron
