Bridging Course Flashcards
Alkali Metals (+1)
Lithium (Li)
Sodium (Na)
Potassium (K)
Rubidium (Rb)
Caesium (Cs)
Alkali Earth Metals (+2)
first group
Beryllium (Be)
Magnesium (Mg)
Calcium (Ca)
Strontium (Sr)
Barium (Ba)
Alkali Earth Metals (+2)
second group
Boron (B) (+3)
Aluminium (Al)
Gallium (Ga)
Indium (In)
Thallium (Tl)
Alkali Earth Metals (+2)
third group
Carbon (C) (+4)
Silicon (Si)
Germanium (Ge)
Tin (Sn)
Lead (Pb)
Alkali Earth Metals (+2)
fourth group
Nitrogen (N) (+5)
Phosphorus (P)
Arsenic (As)
Antimony (Sb)
Bismuth (Bi)
Alkali Earth Metals (+2)
fifth group
Oxygen (O)
Sulphur (S)
Selenium (Se)
Tellurium (Te)
Halogens (-1)
Fluorine (Fl)
Chlorine (Cl)
Bromine (Br)
Iodine (I)
Noble gases (-2)
are naturally monatomic
Helium (He)
Neon (Ne)
Argon (Ar)
Krypton (Kr)
Xenon (Xe)
Radon (Rn)
Some transition metals (-3)
Chromium (Cr)
Manganese (Mn)
Iron (Fe)
Nickel (Ni)
Copper (Cu)
Zinc (Zn)
Silver (Ag)
Cadmium (Cd)
Platinum (Pt)
Gold (Au)
Mercury (Hg).
Element
substance which cannot be broken down into simpler component substances
Metals (physical)
Shiny when freshly cut
Conduct heat and electricity well
Malleable
Ductile
Non-metals (physical)
Powders or gases
Do not conduct well
Solids will be brittle
Chemical change
whenever a chemical bond is broken or formed
Physical change
when mixtures are separated into their pure components by physical methods such as filtration, distillation or even by making use of the different densities of components
Mixture
consists of different elements or compounds which have been physically mixed together (e.g. rocks and sand)
inherently impure
Compound
A combination of substances. At least two or more different types of atoms are joined together by chemical bonds
Atom
smallest possible unit of an element. Each elements atoms are unique to each element
Molecule
atoms bonded together (e.g. CO2)
Allotrope
the various forms in which an element may occur. An element may occur with more than one arrangement of its constituent atoms.
Monatomic
contain one atom
Diatomic
contain 2 atoms
Triatomic
contain 3 atoms
In what fundamental way do compounds differ from elements?
Elements are naturally occurring substances and cannot be reduced to a simpler form, whereas compounds are a combination of these substances with at least 2 different types of atoms that are chemically bonded
Can one write a formula for air? Explain why.
No because it is a mixture of elements (oxygen, nitrogen and argon) and compounds (carbon dioxide and water vapour) and this mixture will vary depending on samples so there is no set formula
The formula for the molecule of water is H2O. Is this an example of a diatomic or a triatomic molecule? Justify your answer.
It would be known as a triatomic molecule because there are 3 atoms in total that makeup the molecule.
The molecule of the element chlorine is written as Cl2. Why is this preferable as opposed to writing it as 2Cl?
This is because Cl2 exists as diatomic in nature and by saying 2Cl you would be saying that there is two chlorine atoms that are NOT chemically bonded
Homogenous
pure compound
Electrolysis
the process of using electricity to split water into hydrogen and oxygen
mixtures are…
heterogenous
mass of a single atom
10^-24 - 10^-21 g
Proton
1.673 × 10^–24 g
+1
Electron
0.0009 × proton mass = 0.0009 × 10^–24 g
-1
Neutron
1.675 × 10^–24 g
no charge
Nucleus
contains protons and neutrons
Alpha particle
2 protons and 2 neutrons joined together, very strongly ionising
Beta particle
electron, quite strongly ionising
Gamma
types of electromagnetic radiation, travels far in air, weakly ionising, no charge, absorbed in Earth’s atmosphere
Ionising power
when radiation collides with atoms, it can cause the atoms to lose electrons and form ions
Positron
same mass as an electron, +1
Positron decay
when nucleus has to many protons it becomes unstable and needs to decay to get rid of excess protons
β+ particle
high speed electron
Avogadro’s number
1 mole = 6.022 x 10^23
Nuclear decay
When an isotope has significantly more or less neutrons than the number of protons in its nucleus, it is usually unstable and undergoes a nuclear spontaneously over a period of time - radioactive species
Nuclear force
operating between protons, between neutrons and between protons and neutrons is the reason why the nucleus is stable provided there is an appropriate ratio of protons to neutrons.
It is a nuclear force and is not experienced by electrons.
Electron energy
Electrons occupying orbits closest to the nucleus have the lowest energy while electrons in orbits further out from the nucleus have higher energy.
This is because, in order to overcome electrostatic attraction to the nucleus, energy must be supplied to an electron to move it from an orbit closer to the nucleus to an orbit further out
atomic radius
the larger the atomic number of an atom, the more electrons it will have and the larger will be its atomic radius
Ground state
When all electrons in a given atom occupy the lowest possible energy orbits
Excited state
one or more electrons can jump to occupy a higher energy orbit for a brief period
Electromagnetic radiation
energy released by excited electrons returning to lower energy orbits
The pattern of lines observed is the atomic emission spectrum
1st orbit level
can only hold 2 electrons
2nd orbit level
can hold 8 electrons
Noble gases are referred to as inert because…
they do not normally enter into any chemical reactions
atoms of noble gases require too much energy to be involved in any redistribution of electrons with other atoms
Ion
When an atom acquires a charge and is no longer electrically neutral
Cation
ions which have a positive charge
Anion
ion has a negative charge
ide
suffix added to the name of the element to show that it is in a form an anion
isoelectronic
When atoms of different elements attain the same electron arrangement by forming cations or anions
metals form…
cations
non-metals form…
anions
is ionisation energy spontaneous?
No, formation of cations from metal atoms requires this energy input
