section 1 Principles of chemistry Flashcards
what are the 3 different forms of material?
solid
liquid
gas
in a solid the particles don’t …………..
move
the hotter the particles are the ………………… they move
faster
do liquids have a definite shape or volume?
volume
in gases particles move in a ……………… motion
random
what is the process where a solid is cooled to make a gas called?
subliming
what is condensing and evaporating?
condensing - cooling a gas to a liquid
evaporating - heating a liquid to a gas
what does ammonia and HCL create in a glass tube?
a white ring of ammonium chloride
what is in a nucleus of an atom?
protons and neutrons
where are electrons in an atom?
on the outer shells
what is the mass number?
the number of protons and neutrons
what is the atomic number?
the number of protons or electrons
what is a molecule?
a group of atoms
elements consist of ………………. atom
one type
how are compounds bonded?
chemically
what is filtration used to separate?
insoluble solids from liquid
what is used to separate a soluble solid from a solution?
crystallisation
what are the four steps to separate rock salts
grinding
dissolving
filtering
crystallisation
what is chromatography used for?
identifying dyes
what are the 2 types of distillation and what are they used for?
simple - separate solution
fractional - separate a mixture of liquids (crude oil)
what is group 1, 0 and 7 on the periodic table called?
1 - alkali metals
0 - noble gases
7 - halogens
how many electrons can go on each shell?
2 on the first then 8 on every other one
what is ionic bonding?
transfer of electrons to form ions
giant ionic structures have a …….. melting and boiling point
high
what is covalent bonding?
sharing electrons
how can covalent bonding be shown?
dot and cross diagram
what type of bonding has a very strong attraction?
covalent
is there charged ions in a giant covalent structure?
no
giant covalent structures ……………………. electricity
don’t conduct
give 2 examples of giant covalent structures
diamond
graphite
What type of attraction is there between ionic bonding and what does that give the compounds?
Strong electrostatic bond between the oppositely charged ions giving a high melting and boiling point
How are covalent bonds held together?
Strong attraction between the shared electron and the nuclei of the atoms involved
Explain the attraction in a simple molecular substance
Atoms within a molecule are very strong
Attraction between molecules are very week ( intermolecular)
Melting and boiling points are low
Explain covalent structures
Lots of strong covalent bonds - takes a lot of energy to break
Don’t conduct electricity
Insoluble in water
Eg diamonds and graphite
Compounds with ionic bonding always have ………… And ions are held to get her in a ………………
Giant ionic structures
Closely packed 3d lattice by attraction between oppositely charge ions to
Ionic compounds have a …….. Melting and boiling point because ………………
High
Electrostatic attraction is very strong
Lattices with higher charged ions will ..….…
Have higher Melting and boiling points
Explain the structure of a diamond
Each carbon forms four covalent bonds
Hardest natural substance