States of matter
What is the conversion from solid to gas called?
Sublimation
What subatomic particle has a positive charge?
What type of force holds the ions in ionic bonds?
Electrostatic forces of attraction
How many electrons can the 3rd energy level hold for an element with a proton number more than 20?
18
Which group in the periodic table contains the noble gases?
Group 18 /Group 0 / Group VIII
State two differences between evaporation and boiling.
Evaporation happens at the surface while boiling happens throughout the liquid.
Evaporation takes place at any temperature while boiling takes place at a specific temperature.
Evaporation happens at a slow rate while boiling happens at a fast rate.
What particle is found in the nucleus and has no charge?
Neutrons
Why do metals conduct electricity?
Metals have delocalised free moving/mobile electrons
What is the electron configuration of sulfide ion (atomic number of sulfur = 16)?
2.8.8
Why do simple covalent molecules like water and oxygen have low melting points?
They have weak intermolecular forces which require very little heat to overcome.
State the arrangement, separation and motion of particles in a solid.
Arrangement is lattice
Separation is very close
Motion is vibrating in a fixed position
What are isotopes?
Atoms of the same element with the same number of protons but different numbers of neutrons
Why do ionic compounds conduct only in aqueous or molten state?
In aqueous or molten state ions are free to move
What is the noble gas configuration for a calcium (Ca2+) ion?
2.8.8
State 2 similarities and differences between diamond and graphite?
Both made up of only carbon atoms
Both have high melting points. Diamond is hard while graphite is soft.
Diamond does not conduct electricity while graphite conducts.
What is diffusion?
Random collisions of particles that collide, mix and spread from an area of high concentration to an area of low concentration
State the number of electrons, protons and neutrons in an ion of potassium (K).
K+ ion has 18 electrons, 19 protons and 20 neutrons.
Why do metals have high melting points?
Metals have strong electrostatic forces of attraction that require a lot of heat to overcome
State the location of this element in the Periodic Table based on the electronic structure.
2.8.18.7
The position of the element in the Periodic Table is Group VII
Period 4
Why does diamond and silicon(IV) oxide have high melting points?
Both have many strong covalent bonds that require a lot of heat to overcome.
In a cooling curve, during the freezing and condensation process, temperature stays constant. Explain why.
Energy lost from the molecules is used to form bonds/intermolecular forces of attraction rather than lowering kinetic energy
What is the mass and charge of a proton, neutron and an electron?
Mass of a proton is 1 and charge is +1, mass of a neutron is 1 and no charge while the mass of an electron 1/1840 and charge is -1.
Describe metallic bonding
Lattice of positive metal ions surrounded by sea of delocalised electrons held by strong electrostatic forces of attraction
What is the main reason why noble gases have a stable electronic configuration?
They have a complete outer shell of electrons
Why is graphite soft and slippery?
Weak forces between the layers allows the layers to slide