Bonding Flashcards
What is an ionic bond? (2)
A bond formed from the electrostatic attraction (1) between two ions. (1)
How is an ion formed? (2)
An ion is formed when an atom gains/loses electrons to form a charged atom (1) with a maximum number of outer electrons. (1)
What is meant by a giant ionic structure? (1)
A giant ionic lattice structure in which each ion is surrounded by ions of the opposite charge. (1)
List 3 properties of giant ionic structures. (3)
- High melting and boiling points. (1)
- The ions are in a fixed position and so can’t carry an electric charge. (1)
- When dissolved in water the ions are free to move so they can carry a charge. (1)
Why do ionic substances usually have high melting and boiling points. (1)
The strong electrostatic attraction means a lot of energy is required to break the strong bonds. (1)
Work out the ionic formula for Aluminium Oxide. (2)
Al³⁺ + O²⁻ –> Al₂O₃ (2)
Work out the ionic formula for Iron (II) Chloride. (2)
Fe²⁺ + Cl⁻ –> FeCl₂ (2)
What is a compound ion? (1)
When a compound becomes charged like an ion. (1)
What is the formula for a positive ammonium ion? (1)
NH₄⁺ (1)
What is the formula for a negative hydroxide ion? (1)
OH⁻ (1)
Work out the ionic formula for aluminium nitrate. (2)
Al³⁺ + NO₃⁻ –> Al(NO₃)₃ (2)
What is a covalent bond? (1)
A bond in which the atoms share electrons to achieve a full outer electron shell. (1)
List 2 properties of simple covalent molecules. (2)
- Low melting and boiling points (1)
- Can’t carry an electric charge due to having no charged particles. (1)
Why do simple covalent molecules have low melting and boiling points? (2)
Because the molecules are held together via weak intermolecular forces (1), making them easy to break with enough energy. (1)
What is a giant covalent structure? (1)
When many atoms share electrons to form a large solid structure.(1)
Name 3 examples of giant covalent structures. (3)
- Diamond (1)
- Graphite (1)
- Silicon dioxide (1)
Why do giant covalent structures have high melting and boiling points? (1)
Because they contain many strong covalent bonds that require lots of energy to break. (1)
How is graphite different to other covalent structures? (2)
It’s able to conduct electricity (1) due to having delocalised electrons between the layers. (1)
What is a fullerene? (2)
A hollow cage (1) formed by a finite number of carbon atoms. (1)
How large are nanoparticles? (1)
Between 1-100 nanometres. (1)
How do we work out for surface area to volume ratio in 4 steps? (4)
- Work out the surface area of the shape. (1)
- Work out the volume of the shape (1)
- Write a ratio between the two (1)
- Divide both sides by the volume such that the ratio is in the form n:1 (1)
List 3 limitations to bonding models. (3)
- They are not to scale/not accurate. (1)
- Some indicate 3-dimensionality and some don’t. (1)
- Some show all the electrons and others don’t show all the electrons or energy shells. (1)
How do metals form positive ions? (1)
By losing electrons and becoming positive. (1)
What happens to the electrons lost from the metal ion? (1)
They become delocalised/free to move around. (1)
What is a metallic bond? (2)
A bond formed from the electrostatic attraction (1) between positive metal ions and the delocalised electrons in the metal (1)
Why do metals conduct electricity? (3)
The delocalised electrons (1) within the metal are free to move around (1) and carry a charge. (1)
What is a pure metal? (1)
A metallic substance made up of only one type of metal atom. (1)
What is an alloy? (2)
A metallic substance that is a a mixture of multiple types of metal atoms (as well as a few non-metal atoms) (1) commonly bonded to the delocalised electrons (1)
Why are pure metals soft? (3)
In pure metals, the atoms are all the same size (1) and so they form layers (1) that can slide past each other, making them malleable. (1)
Why are alloys harder than pure metals? (3)
In alloys, the different atoms are all different sizes (1), distorting the layers (1) and making it harder for them to slide past each other. (1)
