Atomic Structure + Bonding Flashcards
(27 cards)
What was the work of Dalton?
He theorised that atoms are like billard balls, little spheres of matter.
What was the work of Thompson?
• He discovered electrons
• Created plum pudding atomic model
What was the work of Rutherford?
• Discovered the charged nucleus
• Created nuclear atomic model
What is an Element’s mass number?
• The number of particles in the nucleus (protons + neutrons)
• Written above the element on a periodic table
What is an Element’s atomic number?
• The number of protons in the nucleus, defines an element (how they’re organised in Periodic table)
• Written below the element on the Periodic table
What is an Isotope?
A version of an element containing a different number of neutrons but the same number of protons.
What is a Relative Atomic Mass?
The weighted average of an element, in account of its isotopes.
How do Atoms become ions?
They lose/gain electrons
What are negative and positive ions called?
Negative Ions = Anions
Positive Ions = Cations
How is the charge of an element determined?
Its group number (number of valency electrons) determines how many electrons it has to lose or gain to form a full outer shell.
How are positive and negative ions formed?
• Positive ions lose electrons (creating positive charge)
• Negative ions gain electrons
Define Ionic Bonding
A strong electrostatic attraction between oppositely charged ions.
Characteristics of Ionic Structures
• All ionic compounds are solids at room temperature
• Takes a large amount of energy to overcome their bonds
• High melting/boiling points
• Soluble in polar liquids
• When molten/ in solution can conduct electricity
• Structures known as Giant Ionic Lattices
How can you represent Ionic Bonding in a diagram?
Drawing a Dot and Cross Diagram
What factors should you consider when evaluating models that represent bonding?
Does it include:
• Names of elements
• Charges
• Ratio of the elements
• Electrons (eg. Dot and Cross)
• Structure/ Arrangement
Advantages and Disadvantages of Formulae
Advantages:
- Simple
- Names elements
- Shows ratio
Disadvantages:
- No electrons/charges
- No structure shown
Advantages and Disadvantages of Dot + Cross Diagrams
Advantages:
- Names elements
- Shows charges + electrons
- Shows ratio of elements
Disadvantages:
- Doesn’t show any of the real structure
Advantages and Disadvantages of 2D Diagrams
Advantages:
- Shows charge
- Shows ratio
- Shows arrangement
Disadvantages:
- Doesn’t name elements
- No electrons shown
Advantages and Disadvantages of 3D Diagrams
Advantages:
- Shows real structure
- Shows ratio between elements
Disadvantages:
- No names
- No charges/electrons
Name 3 Properties of Metals
Any of the following:
• High MP/BP
• Conductors
• Dense
• Malleable
• Ductile
• Sonorous
• Shiny
• Strong
Name 3 Properties of Non-metals
Any of the following:
• Low MP/BP
• Insulators
• Low density
• Brittle
• Dull
What is Metallic bonding?
An electrostatic attraction between positive metal ions and a sea of delocalised electrons.
What are Alloys?
Mixtures of various metals (eg. Bronze is a mixture of Copper + tin)
• Formed without metallic bonding
What are the 2 kinds of Alloy structures?
1) Smaller particles that cause rows to fall out of place and become misaligned
2) Larger particles that disrupt regular patterns
