Inorganic Chemistry Flashcards
What are the four fundamental forces ?
- Strong Nuclear force
- Weak Nuclear force
- Electromagnetic force
- Gravity
What force(s) bind Protons and Neutrons and only goes the distance of an atom ?
- Strong nuclear force
- Weak nuclear force
What force(s) is responsible for the attraction between positive and negative charge ?
Electromagnetic force
What distance can Electromagnetic force travel ?
Its infinite
What force(s) cause the attraction of matter to other matter ?
Gravity
What elements were formed through the big band and what is the proportion of these elements ?
Hydrogen (89%)
Helium (11%)
2 hours After the big band, the universe cooled, what happened next ?
The Strong nuclear force bound protons and neutrons into atomic nuclei and the electromagnetic force pulled the nuclei and electrons together to from atoms.
What happened during Stellar Nucleosynthesis ? and what elements did this create
Gravity brough H and He close together and they compressed which meant the density and heat rose and gave stars. Lighter atoms fused by nuclear fusion- this process also releases energy.
Created elements until Fe
What happened during Supernova Nucleosynthesis ? and what elements did this create
Old stars became very dense and heavier elements such as Oxygen and silicon fused to give very heavy elements. They formed and very ejected by explosion along any previously formed lighter elements.
Elements from Ni to U
What are the ways elements were created ?
- The big bang
- Steller nucleosynthesis
- Supernova nucleosynthesis
- Radioactive decay
- Human interference
What is a group ?
Elements going down the periodic table
What is a period ?
Elements going across a periodic table
What is the ‘Periodic Law’ ?
The properties of elements are periodic functions of their atomic number
Why do elements in the same group have similar chemical properties ?
They have the same number of valence shell electron configuration
Valence shell definition
Outer shell
What is the max. number of electrons in an atomic orbital ?
2
What are the four different types of atomic orbital ?
s, p, d, f
Degenerate
equal energy
What gives the periodic table its structure ?
order of atomic orbitals
What are the three groups of elements?
metals, non-metals and semi-metals
what elements are semi- metals ? (use the periodic table to help)
B, Si, Ge, As, Sb, Te, At
What is ‘Effective Nuclear Charge’ ?
The positive charge than an electron experiences from the nucleus.
What is the trend for effective nuclear charge going across a period ?
ENC increases as nuclear charge increases
What is the trend for effective nuclear charge going down a group ?
ENC decreases as shielding increases- through more occupied energy levels
What is ‘Atomic Radius’ ?
Half the distance between the nuclei in an element
Why is measuring atomic radii trivial ?
They don’t end abruptly as electrons ‘fall away’
What is the trend for atomic radius going down a group?
Atomic Radius increases as a new shell of electrons is added
What is the trend for atomic radius going across a period ?
The Atomic radius decreases as the ENC increases hence there’s more attraction to nucleus, pulling electrons closer to the nucleus.
What is ionisation energy ?
Minimum energy required to remove the outermost (highest energy) electrons from a neutral atom in the gaseous state.
Is an Ionisation reaction exothermic or endothermic ?
Endothermic
What is the trend for ionisation going across a period ?
The ionisation energy increases as the atom size decreases, valence electrons are closer to nucleus hence more energy is required to remove it
What is the trend for ionisation energy going down a group ?
Ionisation energy decreases as The electrons are further from the nucleus so are not tightly bound to the nucleus