Atomic Structure Flashcards
What is matter
Anything we can see smell touch, that occupies space and has mass
What is the mass of an electron
1/1837
What is a molecule
Two or more atoms chemically combined
Eg O2 molecules
What are macromolecules
A very large molecule like DNA or proteins
Label the following with their scientific notation in reference to a metre Cm Mm Um Nm Pm
Cm: centimetres : 10(-2)m Mm: millimetres : 10(-3)m Um: micrometers : 10 (-6)m Nm: nanometers : 10(-9)m Pm: picometres: 10(-12)m
The exponent is the number of zeroes before we get to the 1.
Eg: mm : 0.001 of a metre
What is the maximum width the eye can see?
0.5mm
Width of human hair
Where do atoms originate?
In the stars
What is nanoscience?
Interdisciplinary field studying structures on the nanoscale.
What is so special about things on the nanoscale?
The extremely small size of the nanoparticles gives them unique properties, described using quantum not classical physics.
How does energy occur according the quantum mechanics?
Energy is not continuous but comes in small packets called quanta.
THEY HAVE WAVE PROPERTIES.
What are some uses of nanotech?
Medicine and Pharmaceuticals, designed on the nanoscale for more effective and accurate treatments.
silver socks- antibacterial
Carbon nanotubes- bullet proof vests.
PROPERTY OF THINGS CHANGE ON THE NANOSCALE
What are some cons of nanotech?
Privacy issues
Potential Military use- tiny weapons
Who own nanotech?
Accidental release. we dont really know much about it
Atomic number is
Number of protons in nucleus of atom.
how many elements are there?
118
Mass Number is
total number of protons and neutrons in an element
Label an isotopic symbol
A
Z E a=mass number Z= atomic number E= symbol for element
What are isotopes?
Forms of an element with the same number of protons but a different number of neutrons. May have different physical properties due to different masses.
EG- deuterium h a =2 - used in heavy water makes it denser than regular water
What is a cool use of isotopes?
Radiocarbon dating.
The radioactive isotope carbon-14 has a half life of 5700 years and is present in small amounts in living things. The amount of the isotope left in something can tell us how old it is.
What determines the behaviour and compounds an element makes?
THE ARRANGEMENT OF ELECTRONS AROUND THE NUCLEUS LARGELY determines an atoms behaviour, properties and what compounds/molecules it makes (if any)
What happens when you pass an electric current through the gaseous vapours of an element?
An atomic emission spectrum is produced, because the atoms absorb energy and then lose it as light.
What is an atomic emission spectrum?
a series of separate lines of coloured light. Each line consists of a particular frequency and therefor one exact amount of energy given off by an atom.
What happens when an atom drops back from exited state?
An element gives off the excess energy that it holds as a photon, which is seen as a line of colour on the visible spectrum.
THE ENERGY GIVEN OUT IS THE DIFFERENCE IN ENERGY LEVELS BETWEEN TWO ENERGY LEVELS
What are electrons shells?
REgions of space surrounding the nucleus where electrons move, labelled K,L,M,N and 1,2,3,4.
( lowest energy is k and it increases as you go up in shells)
How many electrons can go into a shell?
2n^2 where n is the number of the shell
What is electron configuration?
Arrangement of electrons in the shells of an atom.
Ions
atoms that have lost or gains one or more electrons
What largely determines the chemical properties of an element?
Outer shell (Valence) electrons, as it determines bonding.
What are some problems with the shell model?
Doesnt explain difference in energy levels.
Implies electrons move around in set paths
What is an orbital?
A region of space around the nucleus.
visualise as a blurry cloud of negative charge, most dense where you are most likely to find an electron.
What is a subshell?
several different energy levels within a shell. n° of subshells equals the number of the shell. subshells are s p d f and they are different shapes. 1 3 5 7
How many electrons can go in a subshell?
0,1,2
Why do nanoparticles have cool properties?
High surface area to volume ratio, and extremely small size.
What is up with chromium and copper?
They have half and fully filled d subshell and only have 4s1.
Why does chromium and copper do that thing?
MORE STABILITY
