Flashcards in C2 Deck (40):
What is relative atomic mass?
Relative atomic mass, Ar, is the mean mass of an element compared to 1/12 the mass of a carbon-12 atom
What is relative formula mass?
Relative formula mass, Mr, is the mean mass of a unit of substance compared to 1/12 the mass of a carbon-12 atom
What is relative molecular mass?
Relative molecular mass, Mr, is the mean mass of a unit of a molecule compared to 1/12 the mass of a carbon-12 atom
Appearance of metals and non-metals
Metals are shiny, non-metals are dull
Melting and boiling point of metals and non-metals
Metals usually have high melting and boiling points, while non-metals are usually low
State at room temperature for metals and non-metals
Metals are solid, non-metals have half solid, half gas
Malleable or brittle when solid for metals and non-metals
Metals are malleable, non-metals are brittle
Ductile or non-ductile when solid for metals and non-metals
Metals are ductile, while non-metals are non-ductile
Thermal and electrical conductivity for metals and non-metals
Metals are good conductors, non-metals are poor conductors
How do metals and non-metals form ions?
Metals lose electrons to form positive ions, while non-metals gain electrons to form negative ions
How do metals and non-metals react with each other?
Metals don't react with each other (mix to form alloys) while non-metals react to produce compounds that consist of molecules
What types of solutions do metals and non-metal oxides form when placed in water?
Metal oxides form alkaline solutions
Non-metal oxides produce acidic solutions
How do ionic compounds form?
When a metal reacts with a non-metal, electrons are transferred from the metal atoms to the non-metal atoms so both achieve more stable electronic structures
How are ionic compounds structured?
Ionic compounds contain positive and negative ions arranged in a regular way. This is called a giant ionic lattice
How are ions in ionic compounds held in place?
Ions are held in place by ionic bonds, which are electrostatic forces of attraction between oppositely charged ions
What are the limitations of dot and cross diagrams?
Dot and cross diagrams don't show the 3D structure
What are the limitations of ball and stick models?
Ions are close together, and bonds are forces rather than physical objects made from matter, size is exaggerated
What are covalent bonds and how do they form?
Covalent bonds are shared pairs of electrons, which form between two non-metal atoms when the atoms get close enough to share electrons, to complete their outer shells
What are simple molecules?
Simple molecules are molecules that contain only a few atoms
What are the forces in covalent bonds?
In covalent bonds, they involve electrostatic forces of attraction between the nucleus of each bonded atom and the shared electrons
The ... between atoms in a simple molecule are ..., but the ... are ...
covalent bonds, strong, intermolecular forces, weak
What are the limitations of a displayed formula?
A displayed formula doesn't show the shape of the simple molecule, or the 3D part of it
What are giant covalent structures?
Giant covalent structures consist of many non-metal atoms joined by covalent bonds
How are atoms arranged in a giant covalent structure?
In a repeating regular pattern called a giant covalent lattice
What are the chemical formulae of giant covalent structures?
They are represented as empirical formulae because there are so many atoms
What are polymers?
Polymers are molecules that join end to end from smaller molecules called monomers
How are polymer molecules modelled?
Polymers are modelled using their monomer form, using dot and cross, space filling and ball & stick models
What are repeating units?
Repeating units are sections of a polymer that is repeated over and over again, rather like links in a chain
What are the structure of metals like?
Metal atoms are packed together in a regular way, forming a giant metallic lattice
How can you model a metal?
By drawing circles or spheres arranged in a regular pattern
What are metallic bonds?
Metallic bonds are the strong electrostatic forces between delocalised electrons and the closely packed, positively charged metal ions
What are the limitations of the isometric diagram of the metal?
An isometric diagram doesn't show the delocalised electrons, and the subatomic particles overlap
What are the limitations of the elevation view of the metal?
It doesn't show the 3D structure of the metal of the metallic bonding it has
How are the reactions of elements related to the arrangement of electrons in the atoms?
As elements lose or gain certain numbers of electrons in order to complete their outer shells in reactions
How are reactions of elements related to the atomic number?
As the number of electrons before the reaction represents the atomic number
Groups 1 and 2 become ... reactive as you go down the group
Group 7 becomes ... reactive as you go down the group
What was Mendeleev's first arrangement of the periodic table?
Mendeleev's arranged all the elements known in order of atomic weight, and he grouped the ones with similar chemical properties
How was Mendeleev's arrangement refined?
He rotated his table so the groups were shown as columns